mavic rims suck?
Steve Knight
now I am a heavy rider (right now about 238 with up to 15 or so pounds on my
back. I use a 25mm tire with full 120 or close pressure.
my last rim was getting out of true a lot and a new derailer slipped a bit and
chewed up the spokes so I replaced the spokes and rim with the ma3.
after about 700 or so miles of daily commuting the wheel needed little trueing
so I did it. the next day it was off again. I was tightening the spokes when I
saw one that looked like it had a hump around it. a closer look reveled that the
rim was cracked around the spoke and it was pulling out.
nothing like making a person mad seeing a new part failing. I was going to get a
cp22 or 33 rim as I have heard they are pretty bullet proof here. one of my
local shops that has a great owner that does not push things told me the mavic's
with the hole sleeves tend do to that. I have read about the creaking these rims
have and some problems. anyone else have this problem?
he let me use a loaner while he orders a good 36 hole replacement rim.
--
Knight-Toolworks & Custom Planes
Custom made wooden planes at reasonable prices
See http://www.knight-toolworks.com For prices and ordering instructions.
(Pete Cresswell)
> a closer look reveled that the
>rim was cracked around the spoke and it was pulling out.
I'm about 220# and I've toasted three Mavic 517s. On each the spokes were
starting to pull out around the ferrules and there were cracks around same. Not
just some ferrules - all of them.
My take is that the 517 just isn't designed for use by somebody my weight. I've
since switched to a 617 (double ferrule) for my rear wheel.
--
PeteCresswell
Qui si parla Campagnolo
rear. >><BR><BR>
<< I was tightening the spokes when I
saw one that looked like it had a hump around it. a closer look reveled that
the
Not uncommon with MA-3s and we have sent all ours back to Mavic, swapped with
OpenPros. Velocity, either Fusion of Deep Vs are nice rims for you. Cheaper
than CXP-33s as well. CXP-22s are 32 hole only.
Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"
Appkiller
> I had a mavic ma3 rim 36 spoke with good spokes on a campy hub on the rear.
> now I am a heavy rider (right now about 238 with up to 15 or so pounds on my
> back. I use a 25mm tire with full 120 or close pressure.
I vary between 200 - 225 and I use Mavic rimmed wheels exclusively.
They are good. Your wheel's build is what was bad. Even tension
would not result in a spoke pulling out unless the tension were overly
high and you took a bad hit.
You should apply your obvious patience and attention to detail (as
evidenced by your planes) to learning how to build a good set of
wheels. I build my own and ride 36 hole CXP 33's on campy 10 hubs and
32 hole OP's also on campy 10.
Yes, there is a known issue with a the "Mavic Creak" attributed
frequently to a loose insert used to align the ends of the hoop for
welding. That can be fixed.
My 33's rock. Go ahead - but get the book (Jobst Brandt's The Bicycle
Wheel) or pay for your local expert to build them up. 14/15 DB
spokes, three cross.
App
Chris
wieghts. I was going to call my LBS this am, and order a MA3/Suzue rear
wheel. I weigh 165. Thanks
Tim McNamara
newsgroup. Most modern bicycle rims are junk being passed off as
"hi-tech" improvements replete with buzzwords and acronyms, etc.
Mavic is the worst offender of all, IMHO. Look for the Torelli
Master in polished aluminum.
Tim McNamara
The MA3- indeed the entire Mavic line IMHO- is crap. The last good
Mavic rim was the MA2 in polished aluminum. There are vocal
defenders of Mavic who will rise to this as they always do, but
frankly if you're over about 140 lbs stay away from this company's
products. If you can, stay away from anodized rims as they are prone
to early failure by cracking around the spoke holes.
Tim McNamara
> Steve Knight <ste...@knight-toolworks.com> wrote in message
> news:<3dmr209ktv8m9v8kr...@4ax.com>...
>> I had a mavic ma3 rim 36 spoke with good spokes on a campy hub on
>> the rear. now I am a heavy rider (right now about 238 with up to
>> 15 or so pounds on my back. I use a 25mm tire with full 120 or
>> close pressure.
>
> I vary between 200 - 225 and I use Mavic rimmed wheels exclusively.
> They are good. Your wheel's build is what was bad. Even tension
> would not result in a spoke pulling out unless the tension were
> overly high and you took a bad hit.
Malarkey. The rim didn't crack because of excessive spoke tension or
"taking a bad hit" (which can't crack a rim in this manner). The rim
cracked because it is a badly designed POS. So-called "single
eyelets" and anodizing are a particularly bad combination. If you are
a featherweight then you'll probably not have much trouble.
There's been hundreds of threads on this and thousands of posts. You
can read then via Google.
Mike S.
"Tim McNamara" <tim...@bitstream.net> wrote in message
news:m2lln5d...@Stella-Blue.local...
<sarcasm on> OH MY GOD THE SKY IS FALLING! That there are probably
millions of Mavic's anodized rims in the world working well is besides the
point, huh? I myself have 3 pair of anodized Mavic rims, are you saying
you're going to pay to have them rebuilt with Velocity rims?
<Sarcasm off>
Seriously now, eventually everything will fail. If you over-tension your
rims, ride them into potholes, weigh a bunch, etc. you're going to have a
shorter rim lifespan than someone that weighs 135 and floats over things.
I'm running between 170 and 185 depending on what part of the racing season
I'm in. I have a pair of MA40 wheels, a pair of GL330 wheels, and a pair of
Reflex wheels. All are in fine condition.
I'm of the opinion that more depends on how you build the wheel than the rim
itself.
Yes, there are rims that aren't as good for their intended applications, but
for the 165# guy wanting to ride MA3s, I'd say go for it. Personally, I
like MA40s better, but hey, MA3s work too. Alternatives are Torelli Master
rims, and several others that someone else is about to chime in with.
That help?
Mike
Mike S.
'scuse me, but exactly how many of these "crap" rims do you actually have
personal experience with?
...or are you just spouting off stuff you've read on the internet?
Mike
Zog The Undeniable
> The MA3- indeed the entire Mavic line IMHO- is crap. The last good
> Mavic rim was the MA2 in polished aluminum. There are vocal
> defenders of Mavic who will rise to this as they always do, but
> frankly if you're over about 140 lbs stay away from this company's
> products. If you can, stay away from anodized rims as they are prone
> to early failure by cracking around the spoke holes.
I have a pair of Open 4CD rims that were built into wheels (by me,
probably fairly badly) nearly a decade ago. I jump potholes, ride off
kerbs and weigh 180lb. There is no sign of cracking. Maybe the problem
is Mavic quality control and some bad ones are getting through?
I have no particular love for Mavic and would just as readily use Campag
rims...except they've discontinued my favourite Omegas.
Matt O'Toole
> 'scuse me, but exactly how many of these "crap" rims do you actually
> have personal experience with?
Personal experience is not necessary. Anyone with half an education in
mechanical engineering and/or materials science can assess the damage and tell
what caused it. One would hope Mavic would be doing this, but apparently they
don't care. Imagine that -- a business who doesn't care as long as the product
still sells...
> ...or are you just spouting off stuff you've read on the internet?
Crack a book on the subject, or take an engineering class, and you'll be able to
"spout off" too.
Matt O.
Steve Knight
>You should apply your obvious patience and attention to detail (as
>evidenced by your planes) to learning how to build a good set of
>wheels. I build my own and ride 36 hole CXP 33's on campy 10 hubs and
>32 hole OP's also on campy 10.
I did not build the wheel I had a local shop do it. they guys have been doing it
for 20 years and are really good.
but my rides are a bit rough as the streets are not always flat (G)
Steve Knight
>don't care. Imagine that -- a business who doesn't care as long as the product
>still sells...
it's sad but corporations show this fact a lot.
Chris B.
wrote:
>Mike S. wrote:
>
>> 'scuse me, but exactly how many of these "crap" rims do you actually
>> have personal experience with?
>
>Personal experience is not necessary. Anyone with half an education in
>mechanical engineering and/or materials science can assess the damage and tell
>what caused it. One would hope Mavic would be doing this, but apparently they
>don't care. Imagine that -- a business who doesn't care as long as the product
>still sells...
Which lays the blame for the ongoing shittiness of the rims at the
blind brand loyalist's feet. Unfortunately, even companies who are
willing to make products which aren't junk are forced to jazz them up
with silly features to stay in the market. It's a sad state of
affairs for people who want equipment that is reasonably durable.
G.T.
618, I use them, too. My 517 split down the inside of the spoke bed.
Greg
--
"Destroy your safe and happy lives before it is too late,
the battles we fought were long and hard,
just not to be consumed by rock n' roll..." - The Mekons
basjan
> The MA3- indeed the entire Mavic line IMHO- is crap. The last good
> Mavic rim was the MA2 in polished aluminum. There are vocal
> defenders of Mavic who will rise to this as they always do, but
> frankly if you're over about 140 lbs stay away from this company's
> products. If you can, stay away from anodized rims as they are prone
> to early failure by cracking around the spoke holes.
I weigh 205lbs, use Mavic Open Pros, built by myself, a novice. 3000 miles
and no problems whatsoever...
Mike S.
"Zog The Undeniable" <g...@hhh.net> wrote in message
news:c0lnll$hmd$1...@newsg4.svr.pol.co.uk...
Mmmmmm Omega XLs......
I'm STILL trying to find a pair. I found some tubies, but no clinchers.
Oh well.
Mike
Mike S.
"Chris B." <bikerider@-no-spam-thankyou-rogers.com> wrote in message
news:3a1t20tnpon247f9e...@4ax.com...
How F#$%-ing reasonably durable do you want? For every person spouting off
with "Mavic is crap!" there are hundreds of rims out there with NO PROBLEMS.
I know of guys riding new Mavic rims, old Mavic rims, and even somewhere in
the middle. More often than not, the reason they get replaced is accidents.
I'm not particularly enamored of Mavic rims, but bashing them constantly is
getting on my nerves. I'd suggest that we take a poll of how long we've
been riding Mavic rims and the problems we've had.
I've had two Mavic rims in 18 years of riding that failed by cracking at the
nipples. The rest of the wheels I've ever ridden have been fine.
You?
Mike
Mike S.
"Matt O'Toole" <ma...@deltanet.com> wrote in message
news:8BtXb.5262$wD5....@nwrddc03.gnilink.net...
> Mike S. wrote:
>
> > 'scuse me, but exactly how many of these "crap" rims do you actually
> > have personal experience with?
>
> Personal experience is not necessary. Anyone with half an education in
> mechanical engineering and/or materials science can assess the damage and
tell
> what caused it. One would hope Mavic would be doing this, but apparently
they
> don't care. Imagine that -- a business who doesn't care as long as the
product
> still sells...
So you ARE talking out your ass. Gotcha.
>
> > ...or are you just spouting off stuff you've read on the internet?
>
> Crack a book on the subject, or take an engineering class, and you'll be
able to
> "spout off" too.
>
> Matt O.
>
Maybe I've been "lucky" in the 18 years I've been riding, but somehow I
doubt it... See my post above re: poll.
Mike
charles ramsey
They do make 32 hole and 36 hole rims that will take that much abuse.
Go to bikelist.org and do a search under fir rialto one guy is using
this rim with 24 spokes on his triple.
Chris B.
wrote:
>"Chris B." <bikerider@-no-spam-thankyou-rogers.com> wrote in message
>news:3a1t20tnpon247f9e...@4ax.com...
<snip>
>> Which lays the blame for the ongoing shittiness of the rims at the
>> blind brand loyalist's feet. Unfortunately, even companies who are
>> willing to make products which aren't junk are forced to jazz them up
>> with silly features to stay in the market. It's a sad state of
>> affairs for people who want equipment that is reasonably durable.
>
>How F#$%-ing reasonably durable do you want?
Rims which fail by cracking, particularly at the spoke holes are, in
my opinion inferior and unacceptable.
>For every person spouting off with "Mavic is crap!" there are hundreds of rims
>out there with NO PROBLEMS.
The comparison you draw above is meaningless.
Still, I hadn't realized that you have collected data on this; no
wonder you speak so authoritively.
>I know of guys riding new Mavic rims, old Mavic rims, and even somewhere in
>the middle. More often than not, the reason they get replaced is accidents.
More meaninglessness.
>I'm not particularly enamored of Mavic rims, but bashing them constantly is
>getting on my nerves.
Your hysterical defensiveness suggests otherwise.
>I'd suggest that we take a poll of how long we've
>been riding Mavic rims and the problems we've had.
Given your incredible outrage, I would have thought that you had
collected lots of data on this.
Yet you accuse others of 'spouting off'.
If you are serious about using this newsgroup as a method of data
collection, some Google groups searching will produce plenty of
results - with a ton of complaints about Mavic rims cracking about the
spoke holes.
I'll admit that I find it extremely humourous that the many victims of
cracked Mavic rims repeatedly go back for more. It's like a cult.
>I've had two Mavic rims in 18 years of riding that failed by cracking at the
>nipples. The rest of the wheels I've ever ridden have been fine.
You have said essentially nothing here. I could explain why, but I
think it would be a waste of time as you have shown time and time
again that you are simply an airhead.
>You?
My grandmother smoked her whole life and never got cancer.
Appkiller
> The MA3- indeed the entire Mavic line IMHO- is crap.
Hmmm..... your opinion. Be it ever so humble. I'm curious - what do
you ride? Please tell me so I can post that they suck - whether they
do or not - and we can argue about whether your rims'manufacturer's
marketing department is better than mine.
Your sweeping generalization is almost as valuable as my N of 4.
App
Benjamin Lewis
> Maybe I've been "lucky" in the 18 years I've been riding, but somehow I
> doubt it... See my post above re: poll.
Doesn't sound to me like you've been lucky -- you just said in a previous
post that you've had two Mavic rims crack at the eyelets in 18 years. It
sounds like you just have lower expectations from your rims.
--
Benjamin Lewis
Dinosaurs aren't extinct. They've just learned to hide in the trees.
G.T.
>
>
> I've had two Mavic rims in 18 years of riding that failed by cracking at the
> nipples. The rest of the wheels I've ever ridden have been fine.
>
> You?
>
Other than Mavics the only rim I've had fail was an Araya RM-20 that
eventually wore through the braking surface. I have had spokes pull
through a Mavic X-517, I've had a 517 split along spoke holes underneath
the rim strip, and I have 4 friends that have had both happen. Sorry, but
neither of these types of failure should happen on ANY rim.
dianne_1234
<bikerider@-no-spam-thankyou-rogers.com> wrote:
>Rims which fail by cracking, particularly at the spoke holes are, in
>my opinion inferior and unacceptable.
How *should* rims fail?
Cracking at spoke holes is just one common failure mode. A few others
I've seen are:
- brake wall wear
- sidewall fracture
- crashes
Cracks at spoke holes are most often fatigue cracks, not overload.
Different rims can last for greater or fewer cycles before this
happens. Many factors go into how long: anodizing, wall thickness,
knit lines in the extrusion, single eyelets or double, spoke tension
and number, etc.
How many cycles do you want? What compromises are you willing to
tolerate?
G.T.
> On Sat, 14 Feb 2004 23:21:48 GMT, Chris B.
> <bikerider@-no-spam-thankyou-rogers.com> wrote:
>
>
>>Rims which fail by cracking, particularly at the spoke holes are, in
>>my opinion inferior and unacceptable.
>
>
> How *should* rims fail?
>
> Cracking at spoke holes is just one common failure mode.
Cracking at the spoke hole from running proper tension shouldn't be a
"common failure mode".
Matt O'Toole
> How *should* rims fail?
Wearing out at the sidewalls. Hopefully they'll be measured for wear, and
retired before they actually fail. Mavic rims rarely make it that far these
days though, due to design and manufacturing flaws (especially cracking at the
spoke holes).
Matt O.
Mike S.
"G.T." <eth...@sbcglobal.net> wrote in message
news:qPyXb.12762$0W3....@newssvr29.news.prodigy.com...
WAY back when!
Mike
Mike S.
"Matt O'Toole" <ma...@deltanet.com> wrote in message
news:UGzXb.22647$1S1....@nwrddc01.gnilink.net...
ever. Mtn rims, yes.
Most of the road rims I've gone thru were destroyed in crashes.
Mike
Mike S.
"Benjamin Lewis" <bcl...@cs.sfu.ca> wrote in message
news:yy7o1xox...@css.css.sfu.ca...
> Mike S. wrote:
>
> > Maybe I've been "lucky" in the 18 years I've been riding, but somehow I
> > doubt it... See my post above re: poll.
>
> Doesn't sound to me like you've been lucky -- you just said in a previous
> post that you've had two Mavic rims crack at the eyelets in 18 years. It
> sounds like you just have lower expectations from your rims.
>
Mike
David Reuteler
: ?? 2 rims cracking at the eyelets in 18 years is low expectations?
for me that'd be a 25% failure rate. probably need to quantify that
statement.
--
david reuteler
reut...@visi.com
Mike S.
> On Sat, 14 Feb 2004 13:47:54 -0800, "Mike S." <mikeshaw2@coxDOTnet>
> wrote:
>
> >"Chris B." <bikerider@-no-spam-thankyou-rogers.com> wrote in message
> >news:3a1t20tnpon247f9e...@4ax.com...
>
> <snip>
>
> >> Which lays the blame for the ongoing shittiness of the rims at the
> >> blind brand loyalist's feet. Unfortunately, even companies who are
> >> willing to make products which aren't junk are forced to jazz them up
> >> with silly features to stay in the market. It's a sad state of
> >> affairs for people who want equipment that is reasonably durable.
> >
> >How F#$%-ing reasonably durable do you want?
>
> Rims which fail by cracking, particularly at the spoke holes are, in
> my opinion inferior and unacceptable.
>
chance that my rims MAY crack at the nipples for the lighter weight.
> >For every person spouting off with "Mavic is crap!" there are hundreds of
rims
> >out there with NO PROBLEMS.
>
> The comparison you draw above is meaningless.
>
So is spouting off that Mavic rims are crap. SOME Mavic rims ARE crap, but
not all of them...
> Still, I hadn't realized that you have collected data on this; no
> wonder you speak so authoritively.
>
> >I know of guys riding new Mavic rims, old Mavic rims, and even somewhere
in
> >the middle. More often than not, the reason they get replaced is
accidents.
>
> More meaninglessness.
>
> >I'm not particularly enamored of Mavic rims, but bashing them constantly
is
> >getting on my nerves.
>
> Your hysterical defensiveness suggests otherwise.
Hysterical, huh? If you only knew... The only thing hysterical here is
someone waving their hands in the air proclaiming that Mavic rims are crap.
See above.
> >I'd suggest that we take a poll of how long we've
> >been riding Mavic rims and the problems we've had.
>
> Given your incredible outrage, I would have thought that you had
> collected lots of data on this.
>
> Yet you accuse others of 'spouting off'.
>
> If you are serious about using this newsgroup as a method of data
> collection, some Google groups searching will produce plenty of
> results - with a ton of complaints about Mavic rims cracking about the
> spoke holes.
>
Yeah, you hear about the rims cracking. What you DON'T hear is the millions
of rims out there NOT cracking. Cannondales cracked, other things crack,
more often than not 99.9% of whatever it is is perfectly fine. Its the
failures we hear about 'cause people are pissed. How many times has someone
written to this NG and said "My rims are the BEST thing since sliced bread?
Anyone?
> I'll admit that I find it extremely humourous that the many victims of
> cracked Mavic rims repeatedly go back for more. It's like a cult.
>
> >I've had two Mavic rims in 18 years of riding that failed by cracking at
the
> >nipples. The rest of the wheels I've ever ridden have been fine.
>
> You have said essentially nothing here. I could explain why, but I
> think it would be a waste of time as you have shown time and time
> again that you are simply an airhead.
>
> >You?
>
> My grandmother smoked her whole life and never got cancer.
So, I have a friend whose father committed suicide when he was in HS. Drank
like a fish, smoked like a chimney. Perfect liver and lungs. My
grandfather on the other hand, has emphysema. So, a statistical sampling
says that if you smoke, you've got a 2/3rds chance of being fine, right?
Don't think so.
I will say one more time: I don't particularly like Mavic rims. They're
just OK. There are other things out there that perform as well or better.
I would like the Velocity rims too and the two pair I have are fine.
You never did answer the question "what are you riding?"
Mike
jobst....@stanfordalumni.org
> Yeah, you hear about the rims cracking. What you DON'T hear is the
> millions of rims out there NOT cracking. Cannondales cracked, other
> things crack, more often than not 99.9% of whatever it is is
> perfectly fine. Its the failures we hear about 'cause people are
> pissed. How many times has someone written to this NG and said "My
> rims are the BEST thing since sliced bread? Anyone?
If you looked at more wheels than your own, and over a longer time,
you would be aware that cracked rims with socketed spoke holes were
unknown before the great Mavic introduction of hard anodized rims. At
that time I had a large sampling of such failures among the riders in
my group who came by to repair and build wheels.
Just because YOU don't hear of them doesn't mean they aren't
occurring. My experience goes back to the days when all racers rode
tubulars and most rode rims that weighed around 300g. Cracked rims
were not an issue, regardless of whether they got smashed on obstacles
or not. These same riders had plenty of cracked rims after anodizing
became the rage. Here on this newsgroup, when I first pointed out
that hard anodizing caused cracks, riders swore up and down that the
"HARD" anodized rims were stiffer, citing phrases from Mavic
advertisements. They did as if they could feel rim stiffness and that
it was beneficial. Just the same, rims cracked often in spite of
people who defended hard anodizing as the best thing since indexed
shifting.
I find amazing that Mavic has not backed off of entirely from
anodizing instead of cutting down on thickness, but then what are they
going to sell to the aficionados of high-tech. Maybe with the advent
of carbon rims, polished aluminum may surface again for the rest of
bicycling.
>> I'll admit that I find it extremely humourous that the many victims
>> of cracked Mavic rims repeatedly go back for more. It's like a
>> cult.
Oh! Where do you expect them to go? Sensible rims are no longer on
the market, they being to inexpensive and mundane. Bicycling is more
fashion than function for most of the market. Some of those who buy
the stuff are swept up in it by coincidence, not having any
information that it could be different. Just look at sloping top
tubes. They are said to give more safety for the genitals with a
higher stand-over height, when in fact the design allows frame
builders to make only two or three sized to fit all, using looooong
seat posts.
Your tenor reminds me of those who claim that carbon parts are as
reliable as steel and aluminum ones because we don't see a lot of
pictures and reports of failures. The sampling you have is not a
valid basis for such claims and calling others names over it adds
to the skepticism over your motives.
Jobst Brandt
jobst....@stanfordalumni.org
David L. Johnson
> Other than Mavics the only rim I've had fail was an Araya RM-20 that
> eventually wore through the braking surface. I have had spokes pull
> through a Mavic X-517, I've had a 517 split along spoke holes underneath
> the rim strip, and I have 4 friends that have had both happen. Sorry, but
> neither of these types of failure should happen on ANY rim.
Eventually, rims fail. So does everything else, but rims get a lot of
abuse, and eventually will die somehow. Perhaps the only "acceptable"
failure is for the braking flats to wear away, but even if that happens,
someone will complain.
If I get 3 good seasons on a rim, I think that is doing well. Geez, they
don't cost that much, after all, and 10-15k miles is fair value for a $30
(tops) part. I don't think a spoke should ever pull through an eyelet
(and I have had that happen), but other than that, once a rim has served
its due, let it go.
--
David L. Johnson
__o | the people can always be brought to the bidding of the leaders.
_`\(,_ | That is easy. All you have to do is tell them they are being
(_)/ (_) | attacked, and denounce the peacemakers for lack of patriotism
and exposing the country to danger. It works the same in any
<country. -- Hermann Goering
David L. Johnson
> Cracking at the spoke hole from running proper tension shouldn't be a
> "common failure mode".
True. Most of the rims I have had to give up on have been due, if not to
crashes, to dents caused by hitting potholes. The rims that fail at the
spokes I considered to be poor choices.
--
David L. Johnson
__o | It is a scientifically proven fact that a mid life crisis can
_`\(,_ | only be cured by something racy and Italian. Bianchis and
(_)/ (_) | Colnagos are a lot cheaper than Maserattis and Ferraris. --
Glenn Davies
G.T.
> On Sun, 15 Feb 2004 00:12:06 +0000, G.T. wrote:
>
>
>>Other than Mavics the only rim I've had fail was an Araya RM-20 that
>>eventually wore through the braking surface. I have had spokes pull
>>through a Mavic X-517, I've had a 517 split along spoke holes underneath
>>the rim strip, and I have 4 friends that have had both happen. Sorry, but
>>neither of these types of failure should happen on ANY rim.
>
>
> Eventually, rims fail. So does everything else, but rims get a lot of
> abuse, and eventually will die somehow. Perhaps the only "acceptable"
> failure is for the braking flats to wear away, but even if that happens,
> someone will complain.
>
> If I get 3 good seasons on a rim, I think that is doing well. Geez, they
> don't cost that much,
Well, when you're riding off-road 15 miles from the nearest highway and an
8" long split rips open in your rim then cheap replacement cost is not
really a benefit.
Tim McNamara
> "Tim McNamara" <tim...@bitstream.net> wrote in message
> news:m2ptchd...@Stella-Blue.local...
>
>> This has been discussed in literally thousands of posts in this
>> newsgroup. Most modern bicycle rims are junk being passed off as
>> "hi-tech" improvements replete with buzzwords and acronyms, etc.
>> Mavic is the worst offender of all, IMHO. Look for the Torelli
>> Master in polished aluminum.
>
> 'scuse me, but exactly how many of these "crap" rims do you actually
> have personal experience with?
>
> ...or are you just spouting off stuff you've read on the internet?
Sorry, Mike. That conversation has been had too, complete with a list
of rims that have failed in personal use od the use of people I know
and ride with. If you're really interested, rather than just being
gratitously challenging, it's in the archives at Google.
Tim McNamara
Yes. Rims shoul dnot fail by cracking around the spoke holes.
Period.
Ah, this thread is like deja vu all over again.
Tim McNamara
> "Tim McNamara" <tim...@bitstream.net> wrote in message
> news:m2lln5d...@Stella-Blue.local...
>> "Chris" <tut...@gls3c.com> writes:
>>
>> > Are you saying the MA3 is not a good rim overall, or not suited
>> > for heavier wieghts. I was going to call my LBS this am, and
>> > order a MA3/Suzue rear wheel. I weigh 165. Thanks
>>
>> The MA3- indeed the entire Mavic line IMHO- is crap. The last good
>> Mavic rim was the MA2 in polished aluminum. There are vocal
>> defenders of Mavic who will rise to this as they always do, but
>> frankly if you're over about 140 lbs stay away from this company's
>> products. If you can, stay away from anodized rims as they are
>> prone to early failure by cracking around the spoke holes.
>
> <sarcasm on> OH MY GOD THE SKY IS FALLING! That there are probably
> millions of Mavic's anodized rims in the world working well is
> besides the point, huh? I myself have 3 pair of anodized Mavic
> rims, are you saying you're going to pay to have them rebuilt with
> Velocity rims? <Sarcasm off>
Why would I pay to correct your poor choice in rims? That's the most
dumb-ass thing you've written yet among the whoppers you've dropped
in this thread.
> Seriously now, eventually everything will fail. If you over-tension
> your rims, ride them into potholes, weigh a bunch, etc. you're going
> to have a shorter rim lifespan than someone that weighs 135 and
> floats over things.
Everything will eventually fail, the question is whether it fails in
an appropriate mode. Since rim designs that do not fail by cracking
at the spoke holes are readily achieved at no weight penalty compared
to the majority of rims that do, such failure is an inappropriate
mode.
You betray ignorance about wheels when you talk about overtensioning
as a contributor to shortened service life of rims. It is not. Dito
when you seem to claim that hitting bumps causes rims to crack at the
spoke holes- it does not. The information about this is readily
available and you might even enjoy finding out about it. If I damage
a rim in a pothole, I can hardly blame the manufacturer for that, so
that is just another one of your wild red herrings. Weight is
something of an issue in rim service life, however I have put well
over 20,000 miles to date on polished MA2s without failure- but have
never gotten an Open Pro on the rear wheel to last more than 3,000
miles. The Open Pro costs twice as much as the MA2 did and weighs
about the same.
> I'm running between 170 and 185 depending on what part of the racing
> season I'm in. I have a pair of MA40 wheels, a pair of GL330
> wheels, and a pair of Reflex wheels. All are in fine condition.
Good for you. And how many miles do these rims have on them?
20,000? 50,000? 100,000?
> I'm of the opinion that more depends on how you build the wheel than
> the rim itself.
Your opinion, unfortunately, is incorrect. Wheel building technique
has a lot to do with spoke service life, and little to do with rim life.
> Yes, there are rims that aren't as good for their intended
> applications, but for the 165# guy wanting to ride MA3s, I'd say go
> for it. Personally, I like MA40s better, but hey, MA3s work too.
Then you've missed the spate of complaints about failures from
cracking around the spoke holes, apparently. MA40s were famous for
cracking and failing, unlike their non-anodized twins the MA2s.
> Alternatives are Torelli Master rims, and several others that
> someone else is about to chime in with.
I'm glad we agree on the Torelli Master as one candidate.
Tim McNamara
Tim McNamara
> <snip>
>> The MA3- indeed the entire Mavic line IMHO- is crap.
> <snip>
>
> Hmmm..... your opinion. Be it ever so humble. I'm curious - what
> do you ride? Please tell me so I can post that they suck - whether
> they do or not - and we can argue about whether your rims'
> manufacturer's marketing department is better than mine.
Hmm. Let's see. Three pairs of wheels with Mavic MA2s, long gone and
lamented, on various bikes (my race bike, my casual bike and my
cyclo-cross bike). Mileage ranges from 10,000 to 20,000 (except for
the rear rim of one pair, replaced after Northworst Airlines mangled
it en route to PBP. Being unable to find a replacement in France, I
basically had to stomp it straight enough to try to finish PBP. Can't
blame that on Mavic, I guess). I've never cracked an MA2, whereas
I've cracked two Open Pros, an MA 40, a Sun Mistral, two Cosmic
Experts, two X222s- none of them lasting even 3000 miles. OTOH I rode
a pair of Rigida 13-19 27" rims from 1978 to 1990- the first wheels I
ever built. Ruined the front one in a collision, but they were my
only wheels for many years.
Another bike with a mongrel wheel set- the front being a 25 year old
Phil front hub on a Nisi Contender (age and mileage unknown) and the
rear being a Bendix coaster brake laced to an MA3 (with no dish and 36
spokes, I expect it to survive longer than it would in a dished wheel.
I suppose it has about 1500 miles so far, but the anodizing already
showed crazing around the spoke holes under oblique light- so it is
only a matter of time).
And finally a bike with Sun CR16a polished aluminum rims (26", 135
mm/7 speed so almost no dish); eight seasons, about 16,000 miles and
no signs of failure yet.
The variable seems clearly to be anodizing. Every rim I've cracked,
with the exception of the Cosmics, was anodized. Some had single
ferrules and some had nipple sockets. The Cosmics failed for a
different reason- the nipple rides inside a "wedge" that fits inside
the rim, but the profile of the wedge does not quite match the
interior profile of the rim, which concentrates all the stress at two
points.
Mike S.
> "Mike S." <mikeshaw2@coxDOTnet> writes:
>
> > "Tim McNamara" <tim...@bitstream.net> wrote in message
> > news:m2lln5d...@Stella-Blue.local...
> >> "Chris" <tut...@gls3c.com> writes:
> >>
> >> > Are you saying the MA3 is not a good rim overall, or not suited
> >> > for heavier wieghts. I was going to call my LBS this am, and
> >> > order a MA3/Suzue rear wheel. I weigh 165. Thanks
> >>
> >> The MA3- indeed the entire Mavic line IMHO- is crap. The last good
> >> Mavic rim was the MA2 in polished aluminum. There are vocal
> >> defenders of Mavic who will rise to this as they always do, but
> >> frankly if you're over about 140 lbs stay away from this company's
> >> products. If you can, stay away from anodized rims as they are
> >> prone to early failure by cracking around the spoke holes.
> >
> > <sarcasm on> OH MY GOD THE SKY IS FALLING! That there are probably
> > millions of Mavic's anodized rims in the world working well is
> > besides the point, huh? I myself have 3 pair of anodized Mavic
> > rims, are you saying you're going to pay to have them rebuilt with
> > Velocity rims? <Sarcasm off>
>
> Why would I pay to correct your poor choice in rims? That's the most
> dumb-ass thing you've written yet among the whoppers you've dropped
> in this thread.
>
missed that sarcasm thing... Wassamatah? Bifocals need replacing?
> > Seriously now, eventually everything will fail. If you over-tension
> > your rims, ride them into potholes, weigh a bunch, etc. you're going
> > to have a shorter rim lifespan than someone that weighs 135 and
> > floats over things.
>
> Everything will eventually fail, the question is whether it fails in
> an appropriate mode. Since rim designs that do not fail by cracking
> at the spoke holes are readily achieved at no weight penalty compared
> to the majority of rims that do, such failure is an inappropriate
> mode.
>
> You betray ignorance about wheels when you talk about overtensioning
> as a contributor to shortened service life of rims. It is not. Dito
> when you seem to claim that hitting bumps causes rims to crack at the
> spoke holes- it does not. The information about this is readily
> available and you might even enjoy finding out about it. If I damage
> a rim in a pothole, I can hardly blame the manufacturer for that, so
> that is just another one of your wild red herrings. Weight is
> something of an issue in rim service life, however I have put well
> over 20,000 miles to date on polished MA2s without failure- but have
> never gotten an Open Pro on the rear wheel to last more than 3,000
> miles. The Open Pro costs twice as much as the MA2 did and weighs
> about the same.
>
Please point out to me where I said that hitting potholes makes rims crack
at the spoke holes. IIRC, I said "shortened lifespan" not cracking at the
nipples. See above re: reading comprehension.
> > I'm running between 170 and 185 depending on what part of the racing
> > season I'm in. I have a pair of MA40 wheels, a pair of GL330
> > wheels, and a pair of Reflex wheels. All are in fine condition.
>
> Good for you. And how many miles do these rims have on them?
> 20,000? 50,000? 100,000?
>
> > I'm of the opinion that more depends on how you build the wheel than
> > the rim itself.
>
> Your opinion, unfortunately, is incorrect. Wheel building technique
> has a lot to do with spoke service life, and little to do with rim life.
>
> > Yes, there are rims that aren't as good for their intended
> > applications, but for the 165# guy wanting to ride MA3s, I'd say go
> > for it. Personally, I like MA40s better, but hey, MA3s work too.
>
> Then you've missed the spate of complaints about failures from
> cracking around the spoke holes, apparently. MA40s were famous for
> cracking and failing, unlike their non-anodized twins the MA2s.
>
I must've gotten 3-4 good sets of MA40s in my lifetime including the set I'm
riding now. Funny how that works, ain't it?
I don't know how many miles I put on my wheelsets. I keep rotating between
3 sets of training wheels and 3 sets of racing wheels. I'm putting and
average of 12-16 hours/week riding when I'm training, so I do ride my bikes.
My primary wheelset is a pair of Reflex Ceramics that stay on one or the
other of my road bikes. My favorite pair of training wheels is my MA40s
that I built myself.
Benjamin Lewis
> ?? 2 rims cracking at the eyelets in 18 years is low expectations?
Yes. If you're rims don't either fail (if they fail) due to an accident or
from brake pad wear, there's a problem with them.
--
Benjamin Lewis
Although the moon is smaller than the earth, it is farther away.
Mike S.
<jobst....@stanfordalumni.org> wrote in message
news:omBXb.1458$_3.2...@typhoon.sonic.net...
> Mike Shaw writes:
>
> > Yeah, you hear about the rims cracking. What you DON'T hear is the
> > millions of rims out there NOT cracking. Cannondales cracked, other
> > things crack, more often than not 99.9% of whatever it is is
> > perfectly fine. Its the failures we hear about 'cause people are
> > pissed. How many times has someone written to this NG and said "My
> > rims are the BEST thing since sliced bread? Anyone?
>
> If you looked at more wheels than your own, and over a longer time,
> you would be aware that cracked rims with socketed spoke holes were
> unknown before the great Mavic introduction of hard anodized rims. At
> that time I had a large sampling of such failures among the riders in
> my group who came by to repair and build wheels.
>
Between that and riding/racing for 18 years, I'd say I've seen my fair share
of rims. Most of the ones I saw in the shop were there for spoke issues
(bad builds to begin with) or fixing damage from potholes, etc. The vast
minority of rims I saw had any kinds of cracking by the eyelets. Yes, there
were a few, but not many over the years.
> Just because YOU don't hear of them doesn't mean they aren't
> occurring. My experience goes back to the days when all racers rode
> tubulars and most rode rims that weighed around 300g. Cracked rims
> were not an issue, regardless of whether they got smashed on obstacles
> or not. These same riders had plenty of cracked rims after anodizing
> became the rage. Here on this newsgroup, when I first pointed out
> that hard anodizing caused cracks, riders swore up and down that the
> "HARD" anodized rims were stiffer, citing phrases from Mavic
> advertisements. They did as if they could feel rim stiffness and that
> it was beneficial. Just the same, rims cracked often in spite of
> people who defended hard anodizing as the best thing since indexed
> shifting.
>
I didn't ride too before all you could get was anodized rims, but I do
remember a few guys with rims that cracked by the spokes. Could it be that
there used to be 1. less dish (uneven tension) and 2. more spokes? Seems
to me that those two factors would have more to do with cracking at the
eyelet/nipple than most other things. I COULD be wrong. Heaven knows I've
been wrong before...
> I find amazing that Mavic has not backed off of entirely from
> anodizing instead of cutting down on thickness, but then what are they
> going to sell to the aficionados of high-tech. Maybe with the advent
> of carbon rims, polished aluminum may surface again for the rest of
> bicycling.
>
> >> I'll admit that I find it extremely humourous that the many victims
> >> of cracked Mavic rims repeatedly go back for more. It's like a
> >> cult.
>
> Oh! Where do you expect them to go? Sensible rims are no longer on
> the market, they being to inexpensive and mundane. Bicycling is more
> fashion than function for most of the market. Some of those who buy
> the stuff are swept up in it by coincidence, not having any
> information that it could be different. Just look at sloping top
> tubes. They are said to give more safety for the genitals with a
> higher stand-over height, when in fact the design allows frame
> builders to make only two or three sized to fit all, using looooong
> seat posts.
>
> Your tenor reminds me of those who claim that carbon parts are as
> reliable as steel and aluminum ones because we don't see a lot of
> pictures and reports of failures. The sampling you have is not a
> valid basis for such claims and calling others names over it adds
> to the skepticism over your motives.
Oh, and Jobst, you're answering two different posts here...
I am scared of some carbon parts. For some reason, wheels, frames, and
forks are exceptions. I haven't seen or heard of any bars and stems
breaking, BUT... I weigh more than most skinny little euro-racers, so I
tend to run heavier parts than most skinny little euro-racer types.
Mike
>
> Jobst Brandt
> jobst....@stanfordalumni.org
Benjamin Lewis
> On Sun, 15 Feb 2004 00:12:06 +0000, G.T. wrote:
>
>> Other than Mavics the only rim I've had fail was an Araya RM-20 that
>> eventually wore through the braking surface. I have had spokes pull
>> through a Mavic X-517, I've had a 517 split along spoke holes underneath
>> the rim strip, and I have 4 friends that have had both happen. Sorry,
>> but neither of these types of failure should happen on ANY rim.
>
> Eventually, rims fail. So does everything else, but rims get a lot of
> abuse, and eventually will die somehow. Perhaps the only "acceptable"
> failure is for the braking flats to wear away, but even if that happens,
> someone will complain.
>
> If I get 3 good seasons on a rim, I think that is doing well. Geez, they
> don't cost that much, after all, and 10-15k miles is fair value for a $30
> (tops) part. I don't think a spoke should ever pull through an eyelet
> (and I have had that happen), but other than that, once a rim has served
> its due, let it go.
What I *really* object to is that a purported "technological improvement"
on Mavic's part has only two noticeable effects:
- it makes the rim more expensive
- there is very good evidence that it can cause rims to fail
... and yet, strangely enough, Mavic's customers now have no choice but
accepting this "improvement" if they want to buy Mavic's wheels.
Clearly, Mavic has *our* best interests in mind.
Benjamin Lewis
> I don't know how many miles I put on my wheelsets.
Then you have absolutely no basis to your claim that your Mavics are "good
rims" -- and you've even admitted that you destroy enough of your wheels in
crashes, so you have no way of knowing how well they'll hold up for a more
typical rider. Why, then are you going so far out of your way to defend
these rims? One gets a strong feeling that you really just want to
"believe" in these rims, casting aside all logic. What has Mavic done for
you that you come running blindly to their defense like this?
Benjamin Lewis
> Mike S. wrote:
>
>> ?? 2 rims cracking at the eyelets in 18 years is low expectations?
>
> Yes. If you're rims...
^^^^^^
Erk. No one saw that, right?
Damn, now they did.
Benjamin Lewis
> Does working as a mechanic and/or manager of a shop for appx 8 years
> count? Between that and riding/racing for 18 years, I'd say I've seen my
> fair share of rims. Most of the ones I saw in the shop were there for
> spoke issues (bad builds to begin with)
So? Does this mean that those of us who make good wheels ourselves, or
make an effort to get them, should suffer with wheels that only last 1/5 as
long due to an "advance" that makes the wheel cost more? This expensive
technology may not be hurting some people, but it's not helping *anyone*.
Donald Gillies
>What I *really* object to is that a purported "technological improvement"
>on Mavic's part has only two noticeable effects:
> - it makes the rim more expensive
> - there is very good evidence that it can cause rims to fail
>... and yet, strangely enough, Mavic's customers now have no choice but
>accepting this "improvement" if they want to buy Mavic's wheels.
>Clearly, Mavic has *our* best interests in mind.
Hmmm, in the 1970's top quality rims cost $10/ea, $20 a pair. Today,
top-quality rims (open pro silver) costs $60/ea, $120 a pair.
Inflation is up by 6x-7x since the 1970's. I think that rim prices
haven't changed at all, or have even gone down, in the last 20 years.
I read somewhere that today's rims have to be stronger because there
is more dish or stress in a 130 mm hub than in a 120 mm hub. I'm not
sure i believe this, but it could explain the more frequent rim
failures, supposedly, seen today.
What's changed, mostly, is that people are using 28 spokes and radial
or other "aggressive" lacings, and ultralight or exotic spokes. This
puts more stress on each rim ferrule. I wouldn't be surprised if
this has increased rim failures.
It also stands to reason that machined sidewalls either accelerate
failures, or increase rim weight. Machined sidewalls are a cost
saving method for the manufacturers.
- Don Gillies
San Diego, CA
Carl Fogel
[snip]
> I don't know about you, but I've never worn thru the sidewall of a road rim,
> ever. Mtn rims, yes.
>
> Most of the road rims I've gone thru were destroyed in crashes.
>
> Mike
Dear Mike,
Perhaps you're riding in dry conditions?
Here's a link to a post a few months ago
about worn-out road rims:
http://groups.google.com/groups?selm=3fafdb6f%241%40solnews.wv.mentorg.com&output=gplain
Dion Dock's wife wore out three road rims. He
blamed riding in the wet.
Other posts suggest that wet rims pick up grit
from filthy road spray and wear much more quickly
than rims in dry areas.
This is all theoretical to me, with less than
ten inches of rain per year lately and only half
a dozen spots where I touch my brakes on my daily
ride.
Carl Fogel
R15757
<< Cool. Let us know in another 13,000 miles how they're holding up.
>>
Tim, I have more than 20,000 miles on a pair of Open Pros also with no problems
whatsoever, fwiw.
Robert
dianne_1234
wrote:
>dianne_1234 wrote:
>> On Sat, 14 Feb 2004 23:21:48 GMT, Chris B.
>> <bikerider@-no-spam-thankyou-rogers.com> wrote:
>>
>>
>>>Rims which fail by cracking, particularly at the spoke holes are, in
>>>my opinion inferior and unacceptable.
>>
>>
>> How *should* rims fail?
>>
>> Cracking at spoke holes is just one common failure mode.
>
>Cracking at the spoke hole from running proper tension shouldn't be a
>"common failure mode".
The point is, rim cracks at the spoke holes are fatigue failures, and
unless your rim suffers a premature "death" in an accident, with
enough mileage you too might eventually get cracks in your rims. If
not at the spoke holes, then along the brake wall, tire bed or some
other place.
Use causes fatigue.
So one might ask: how many miles do you want before *your* rim cracks?
dianne_1234
wrote:
>dianne_1234 wrote:
>
>> How *should* rims fail?
>
>Wearing out at the sidewalls. Hopefully they'll be measured for wear, and
>retired before they actually fail. Mavic rims rarely make it that far these
>days though, due to design and manufacturing flaws (especially cracking at the
>spoke holes).
>
>Matt O.
It is arguable that *IFF* the spoke holes crack after sufficiently
high mileage, then that may be a safer failure mode than wearing out
the sidewalls.
1. You can see it if you look for it (don't have to measure it) and
2. Complete failure (loss of spoke tension) may be less catastrophic
than failure to catch thin sidewalls (a blow out?).
In my opinion, if the rim lasts "long enough" then the eventual
failure mode is less of a concern for me.
In my opinion the OP has a legitimate beef since his Mavic rim didn't
last very long. But I disagree with others who say that the failure
*mode* should "never" happen.
dianne_1234
>Mike S. <mikeshaw2@coxdotnet> wrote:
>: ?? 2 rims cracking at the eyelets in 18 years is low expectations?
>
>for me that'd be a 25% failure rate. probably need to quantify that
>statement.
Why not accept 100% failure rate? Eventually all rims wear out, either
from sidewalls or other failure modes (say, fatigue cracking).
I think Mike S. lives in San Diego, where it almost never rains.
Should he be expected to wear out the sidewalls?
In dry climates, the other failure modes may become more common.
dianne_1234
<tim...@bitstream.net> wrote:
>You betray ignorance about wheels when you talk about overtensioning
>as a contributor to shortened service life of rims. It is not.
You've got me wondering. Fatigue life is reduced when stress is
increased. Certainly tighter spokes increase the stress in the rim at
the spoke holes.
All other factors equal, tighter spokes should reduce the fatigue life
of both spokes and rim.
>Wheel building technique
>has a lot to do with spoke service life, and little to do with rim life.
Data?
dianne_1234
Thanks. This data does seem to point strongly to anodizing.
One comment: deeper rims are stronger and stiffer. So the airline that
mangled your MA2 may or may not have damaged a deeper rim. It seems
the Open Pro has traded some durability for extra depth (= stiffness
and strength). It's too bad we don't have the MA2 to choose the weaker
and more flexible rim that lasts longer.
dianne_1234
wrote:
>Mike S. wrote:
>
>> ?? 2 rims cracking at the eyelets in 18 years is low expectations?
>
>Yes. If you're rims don't either fail (if they fail) due to an accident or
>from brake pad wear, there's a problem with them.
In my opinion, if rims fail only in those two modes ... then there is
excess weight in them.
Qui si parla Campagnolo
heavier
wieghts. I was going to call my LBS this am, and order a MA3/Suzue rear
Not a good rim in our experience. Eyelets pulling out with normal tension,
front and right side rears. Rider weight seems to have nothing to do with it.
Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"
Qui si parla Campagnolo
defenders of Mavic who will rise to this as they always do, but
frankly if you're over about 140 lbs stay away from this company's
Can only speak from my experience of building a few thousand Mavic rims into
wheelsets. Open Pro, CX-33/22, Reflex are fine and dandy..MA-3s are not.
Tim McNamara
Tim McNamara
> One comment: deeper rims are stronger and stiffer. So the airline
> that mangled your MA2 may or may not have damaged a deeper rim. It
> seems the Open Pro has traded some durability for extra depth (=
> stiffness and strength). It's too bad we don't have the MA2 to
> choose the weaker and more flexible rim that lasts longer.
A polished aluminum Open Pro would be a good product, I think. I'd
certainly give them a try.
Tim McNamara
> <jobst....@stanfordalumni.org> wrote in message
> news:omBXb.1458$_3.2...@typhoon.sonic.net...
>
>> Just because YOU don't hear of them doesn't mean they aren't
>> occurring. My experience goes back to the days when all racers
>> rode tubulars and most rode rims that weighed around 300g. Cracked
>> rims were not an issue, regardless of whether they got smashed on
>> obstacles or not. These same riders had plenty of cracked rims
>> after anodizing became the rage. Here on this newsgroup, when I
>> first pointed out that hard anodizing caused cracks, riders swore
>> up and down that the "HARD" anodized rims were stiffer, citing
>> phrases from Mavic advertisements. They did as if they could feel
>> rim stiffness and that it was beneficial. Just the same, rims
>> cracked often in spite of people who defended hard anodizing as the
>> best thing since indexed shifting.
>>
> I didn't ride too before all you could get was anodized rims, but I
> do remember a few guys with rims that cracked by the spokes. Could
> it be that there used to be 1. less dish (uneven tension) and
> 2. more spokes? Seems to me that those two factors would have more
> to do with cracking at the eyelet/nipple than most other things.
While I think the main culprit is anodizing, I think that more dish
and fewer spokes compound the problem. In a standard 9 speed road
wheel, virtually all the vertical load is borne by the drive side
spokes, the left side being so slack as to contribute almost nothing
to load bearing. IME I have never cracked a *front* rim around the
spoke holes- I think because the load is lower and because there's no
dish.
I have one MA3, bought as an experiment, laced up on a Bendix coaster
brake hub which has no dish (actually, it has about 1 mm reverse
dish). This wheel is on my track bike which I use for occasional
commuting and hill training. This bike only sees about 1,000 miles a
year at most, so it'll be a while before I know how well this rim will
hold up. When I bought this rim, I examined 15 MA3s at the bike shop,
looking at the spoke holes with incident light. Every one of them
showed crazing in the anodized layer around the spoke holes; I bought
the one with the least crazing.
Tim McNamara
> What I *really* object to is that a purported "technological
> improvement" on Mavic's part has only two noticeable effects:
>
> - it makes the rim more expensive
> - there is very good evidence that it can cause rims to fail
>
> ... and yet, strangely enough, Mavic's customers now have no choice
> but accepting this "improvement" if they want to buy Mavic's wheels.
>
> Clearly, Mavic has *our* best interests in mind.
Yes, much like Microsoft also has our best interest in mind.
jim beam
> If you looked at more wheels than your own, and over a longer time,
> you would be aware that cracked rims with socketed spoke holes were
> unknown before the great Mavic introduction of hard anodized rims. At
> that time I had a large sampling of such failures among the riders in
> my group who came by to repair and build wheels.
still beating this dead horse jobst? any chance of you acknowledging
different manufacture or use of different alloys in this time frame?
we've discussed this before but apparently you're not interested in
learning anything.
there are many crack modes for rims, and only one of them is
anodizing-induced fatigue. of all the cracked mavic rims i've seen,
only one has the potential for anodizing to have contributed to its
demise. all the rest have failed due to extrusion defects, stress
corrosion etc.
please, learn a bit more about your subject before asserting "fact" like
this.
jb
jim beam
> The point is, rim cracks at the spoke holes are fatigue failures,
that's a massive oversimplification. classic "fatigue" is usually
trans-granular, i.e. the crack grows perpendicular to the stress and
cuts through individual metal grains. most of the cracked rims i've
seen have failed in an inter-granular way. most of the pics of cracked
rims you see on the web show crack lines to be jagged & "zig-zaggy" as
the fracture follows grain boundry lines. that's an extrusion or stress
corrosion problem.
jb
jim beam
> Hmmm, in the 1970's top quality rims cost $10/ea, $20 a pair. Today,
> top-quality rims (open pro silver) costs $60/ea, $120 a pair.
> Inflation is up by 6x-7x since the 1970's. I think that rim prices
> haven't changed at all, or have even gone down, in the last 20 years.
>
> I read somewhere that today's rims have to be stronger because there
> is more dish or stress in a 130 mm hub than in a 120 mm hub. I'm not
> sure i believe this, but it could explain the more frequent rim
> failures, supposedly, seen today.
>
> What's changed, mostly, is that people are using 28 spokes and radial
> or other "aggressive" lacings, and ultralight or exotic spokes. This
> puts more stress on each rim ferrule. I wouldn't be surprised if
> this has increased rim failures.
>
> It also stands to reason that machined sidewalls either accelerate
> failures, or increase rim weight. Machined sidewalls are a cost
> saving method for the manufacturers.
machined sidewalls are a significant cost burden to manufacturers.
walls are machined because:
1. they're safer - brake pads mate properly with the full braking
surface right out of the shop. no longer do they have to wear to
conformity over time.
2. they're safer - there are no thickness variations around welded seams
that lead to brake grab.
there's no evidence i've seen that machined side walls accelerate
failures. if you have any, please post it.
jb
jim beam
> On Sat, 14 Feb 2004 23:27:07 -0600, Tim McNamara
> <tim...@bitstream.net> wrote:
>
>>The variable seems clearly to be anodizing. Every rim I've cracked,
>>with the exception of the Cosmics, was anodized. Some had single
>>ferrules and some had nipple sockets. The Cosmics failed for a
>>different reason- the nipple rides inside a "wedge" that fits inside
>>the rim, but the profile of the wedge does not quite match the
>>interior profile of the rim, which concentrates all the stress at two
>>points.
>
>
> Thanks. This data does seem to point strongly to anodizing.
but this pic does not:
http://bike-nomad.com/raw_images/p0000401.jpg
here, the right hand crack does _not_ follow the radial crack lines in
the anodizing that are present from the factory. the fact that a crack
propagates tangential to the anodizing cracks, as this pic shows, pretty
much rules out anodizing induced fatigue.
also note the corrosion present.
also note the jagged intergranular crack line.
truth is, you have an alloy that is at the edge of the durability
envelope because it is a compromise to achive superior stiffness &
reduce weight. bontrager's famous "strong, light, durable, choose any
two" quote applies.
David Reuteler
:
:
:>Mike S. <mikeshaw2@coxdotnet> wrote:
:>: ?? 2 rims cracking at the eyelets in 18 years is low expectations?
:>
:>for me that'd be a 25% failure rate. probably need to quantify that
:>statement.
:
: Why not accept 100% failure rate?
the complaint was against the statement "2 rims cracking at the eyelets in
18 years." that's meaningless without numbers. is that a 2% failure rate
or 100%? i don't know. i haven't been given enuf information.
your question is a separate issue entirely.
--
david reuteler
reut...@visi.com
Mike S.
"Benjamin Lewis" <bcl...@cs.sfu.ca> wrote in message
news:yy7oznbk...@css.css.sfu.ca...
> Mike S. wrote:
>
> > I don't know how many miles I put on my wheelsets.
>
> Then you have absolutely no basis to your claim that your Mavics are "good
> rims" -- and you've even admitted that you destroy enough of your wheels
in
> crashes, so you have no way of knowing how well they'll hold up for a more
> typical rider.
Pray tell, define typical!
Riding almost every day means I have a tendency to put on mileage, but just
because I don't track mileage doesn't mean I don't track things: hours
ridden being the big one for me.
I'm a little atypical: I have more than one set of wheels per bike. I'm
atypical that I have a tendency to go faster than 14mph. Atypical in the
sense that I enjoy going fast in a pack of riders and trying to win races.
Atypical in that I've worked in shops for more than a few years. So, yeah,
I'm atypical.
Why, then are you going so far out of your way to defend
> these rims? One gets a strong feeling that you really just want to
> "believe" in these rims, casting aside all logic. What has Mavic done for
> you that you come running blindly to their defense like this?
>
Nothing except that when someone shouts "MAVIC RIMS SUCK" it gets my goat.
You shout "Cannondale Sucks!" and I'd argue that one too. Yes, I agree that
some of Mavic's rims suck. But categorically? That's like saying Bordeaux
wine sucks, or...
Re: Let he who is whithout sin cast the first stone when it comes to calling
someone "blind," hatred works the same way too.
G.T.
More than 800 miles. x517, spokes pulled through. That's pathetic.
Definitely more than 200 miles. X517, split 8" along the spoke holes under
the rim strip. That's really pathetic.
Greg
--
"Destroy your safe and happy lives before it is too late,
the battles we fought were long and hard,
just not to be consumed by rock n' roll..." - The Mekons
Werehatrack
<ste...@knight-toolworks.com> may have said:
> I was tightening the spokes when I
>saw one that looked like it had a hump around it. a closer look reveled that the
>rim was cracked around the spoke and it was pulling out.
This has been reported on a number of occasions, particularly with the
Mavics that have the heavily anodized surfaces. There are some who
feel that there is reason to believe that the anodization may be at
least partially responsible for the failures. I'm not 100% convinced
that the same rim, without the anodizing, wouldn't have the same
failures, though perhaps not as quickly. As a result, I think some of
the Mavics should simply be regarded as being in the "virtual stupid
light" category due to their reported service history.
Your bike shop's advice is, in my estimation, good. Their offer of a
loaner is a stellar recommendation for them.
--
My email address is antispammed; pull WEEDS if replying via e-mail.
Yes, I have a killfile. If I don't respond to something,
it's also possible that I'm busy.
Words processed in a facility that contains nuts.
dianne_1234
Interesting comment, thanks. I have a few questions:
1. How can I differentiate fatigue, SCC and extrusion defects with
ordinary observations tools?
2. Given that spoke tension puts the rim hole under stress even while
not riding, would you expect SCC to crack the rim even without any
riding?
3. Extrusions are rarely solution heat-treated (I understand air or
water cooling is usually as good as it gets for bike rims). Would the
temper have anything to do with the various causes of cracking?
4. I've seen rims crack at the spoke holes in various directions:
Generally circumferentially, generally transversally, and radiating
from the hole in generally "all" directions. Do any of these seem to
be related to the various causes you mention (e.g., SCC, extrusion
defect, etc.)?
5. Does SCC failure require stress + time (to corrode)?
Thanks.
Benjamin Lewis
> So one might ask: how many miles do you want before *your* rim cracks?
I don't want my rims to ever crack. I want to retire it when the sidewalls
get too thin from brake pad wear. This didn't use to be such a high
expectation.
--
Benjamin Lewis
Everything that can be invented has been invented.
-- Charles Duell, Director of U.S. Patent Office, 1899
Benjamin Lewis
Anodizing does not make rims lighter.
jim beam
was built with?
jb
David L. Johnson
> "
>> I didn't ride too before all you could get was anodized rims, but I
>> do remember a few guys with rims that cracked by the spokes. Could
>> it be that there used to be 1. less dish (uneven tension) and
>> 2. more spokes? Seems to me that those two factors would have more
>> to do with cracking at the eyelet/nipple than most other things.
>
> While I think the main culprit is anodizing, I think that more dish
> and fewer spokes compound the problem.
I have experimental evidence of that. When I got back into riding, I
quickly went to 8-speed freewheels, using my old wheels that were
originally 120mm, and put spacers in and had the frame spread to 130. I
re-dished the rear wheels and off I went.
My "better" wheel, with a sub-300g Nisi rim cracked around all the
right-side spoke holes within a few hundred miles.
Unfortunately for the experiment, I did not control for rider weight, but
still I think part of the issue was the dish. These rims were unanodized.
Nisi did have some colored rims at the time, but these were plain
aluminum.
--
David L. Johnson
__o | "What am I on? I'm on my bike, six hours a day, busting my ass.
_`\(,_ | What are you on?" --Lance Armstrong
(_)/ (_) |
G.T.
"jim beam" <u...@ftc.gov> wrote in message
news:vJQXb.13017$i06....@newssvr29.news.prodigy.com...
> greg, can you give us more info on the spoke tension this 800 mile wheel
> was built with?
>
I have no idea of a specific number but why should it matter? Since I don't
have a tensiometer I build my wheels according to Jobst, tensioning it as
high as possible without having the rim warp when stress relieving. Spoke
tension shouldn't be limited by spoke hole strength but by rim strength.
Greg
jim beam
> Interesting comment, thanks. I have a few questions:
>
> 1. How can I differentiate fatigue, SCC and extrusion defects with
> ordinary observations tools?
a magnifying glass 10x or better is readily available and good for
looking at fracture surfaces.
for fatigue, if you look at a "classic" fatigue fracture surface like a
broken crank arm [one that has *not* had the two broken bits placed back
together and ground around like folks do when they're in "look at this!"
mode], you'll get two major zones on the fracture surface. one will be
relatively smooth transgranular surface, typically with "beach marks",
lines where the crack has grown minutely at each stress cycle and leaves
a small striation. the other rough surface where the fatigue crack has
grown sufficiently to start brittle fracture.
for SCC, it's harder because there are different types depending on the
alloy system, but for rims, you'll often you'll get a granular fracture
surface. note that the presence of visible corrosion on a fracture
surface doesn't necessarily indicate it's the cause, just that it's
corroded after cracking! you need a microscope for this one.
extrusion can be surmised from granular cracking along the extrusion
axis, but needs metallography to be sure.
> 2. Given that spoke tension puts the rim hole under stress even while
> not riding, would you expect SCC to crack the rim even without any
> riding?
yes, but this is a compound problem. SCC + fatigue often work together.
sometimes not. depends on the SCC system & the use.
> 3. Extrusions are rarely solution heat-treated (I understand air or
> water cooling is usually as good as it gets for bike rims). Would the
> temper have anything to do with the various causes of cracking?
yes, but it depends. extrusions such as aluminum frame tubes depend
extensively on their heat treatments for their post-weld strength, 6061
for example. 6061 frame tube alloys are similar to rim alloys from what
i understand, so i would expect rims to be heat treated if their joint
is welded, but not sufficiently to affect the grain structure inherited
from its extrusion.
as a terminology aside, for aluminum alloys, it's usually aging, not
tempering. the "solution" part is where the alloy is heated so that its
hardening agents are in "solid solution". it's then quenched,
essentially "freezing" these components in their dissolved state. then
it's aged by reheating to a lower temperature which allows hardening
particles to form from solution. it's like when olive oil goes cloudy
in cold weather. this process may be repeated 2 or even 3 times at
different temps depending on alloy to get the required properties.
> 4. I've seen rims crack at the spoke holes in various directions:
> Generally circumferentially, generally transversally, and radiating
> from the hole in generally "all" directions. Do any of these seem to
> be related to the various causes you mention (e.g., SCC, extrusion
> defect, etc.)?
if you have multiple cracks radiating around the hole in all directions,
that's anodizing. generally, from what i've seen at any rate, actual
metal cracking in a rim like this is pretty rare. [if you have any pics
you could post, that would be great.]
the circumferential stuff is typically extrusion, with maybe a bit of
SCC thrown in to start the ball rolling. i note that mavic 717's now
have a plastic valve hole liner to stop dissimilar metal corrosion where
the brass valve touches the alloy around the valve hole. a number of
the rims i've seen that have cracked internally have started splitting
at exactly this spot. i'm sure being kept wet for extended periods by
absorbent cloth rim tape doesn't help.
> 5. Does SCC failure require stress + time (to corrode)?
yes. but time is a big variable. some agents/alloys will fail rapidly.
others take ages.
there are stress tests where a component has a small quantity of agent
applied and it quickly falls apart as the stress and the agent work
together. watching a residually stressed component like a cold drawn
tube open up like a time-lapse movie of a flower opening is an
impressive sight! there are reasons certain chemicals are not allowed
on planes.
Tim McNamara
> dianne_1234 wrote:
>> On Sat, 14 Feb 2004 23:27:07 -0600, Tim McNamara
>> <tim...@bitstream.net> wrote:
>>
> <snip>
>>>The variable seems clearly to be anodizing. Every rim I've
>>>cracked, with the exception of the Cosmics, was anodized. Some had
>>>single ferrules and some had nipple sockets. The Cosmics failed
>>>for a different reason- the nipple rides inside a "wedge" that fits
>>>inside the rim, but the profile of the wedge does not quite match
>>>the interior profile of the rim, which concentrates all the stress
>>>at two points.
>>
>> Thanks. This data does seem to point strongly to anodizing.
>
> but this pic does not:
>
> http://bike-nomad.com/raw_images/p0000401.jpg
>
> here, the right hand crack does _not_ follow the radial crack lines in
> the anodizing that are present from the factory. the fact that a
> crack propagates tangential to the anodizing cracks, as this pic
> shows, pretty much rules out anodizing induced fatigue.
You can tell this from this photo? Then your eyes or your computer
monitor is better than mine. It looks like a typical situation to
me.
> truth is, you have an alloy that is at the edge of the durability
> envelope because it is a compromise to achive superior stiffness &
> reduce weight. bontrager's famous "strong, light, durable, choose
> any two" quote applies.
Indeed, which is what makes anodizing rims all the more foolish.
jim beam
> "jim beam" <u...@ftc.gov> wrote in message
> news:vJQXb.13017$i06....@newssvr29.news.prodigy.com...
>
>>greg, can you give us more info on the spoke tension this 800 mile wheel
>>was built with?
>>
>
>
> I have no idea of a specific number but why should it matter?
that's like saying "well, my towing hitch is rated at 1200lbs, so i
don't understand why my 5000lb trailer came off going up that hill".
you need to build to spec, otherwise you'll have reliability problems.
> Since I don't
> have a tensiometer
at ~$50, it's affordable. get one.
> I build my wheels according to Jobst, tensioning it as
> high as possible without having the rim warp when stress relieving.
"as high as possible" doesn't mean a lot.
scroll down to "question 1" in the following link:
http://www.damonrinard.com/wheel/index.htm
tension over spec achieves nothing except unreliability.
>Spoke
> tension shouldn't be limited by spoke hole strength but by rim strength.
er, don't you think they're related? [rhetorical]
>
> Greg
>
>
Tim McNamara
> I'm a little atypical: I have more than one set of wheels per bike.
> I'm atypical that I have a tendency to go faster than 14mph.
> Atypical in the sense that I enjoy going fast in a pack of riders
> and trying to win races. Atypical in that I've worked in shops for
> more than a few years. So, yeah, I'm atypical.
Not in this group. Many of us, myself included, have been bikies for
30 years or more. Many of us, myself included, have worked in bike
shops for a living. Many of us, myself included, have raced for 10
years or more. Many of us ride every day (myself not included as it's
below zero and there's a foot of snow on the ground here :-( ). Many
if not most of us have spare wheels for their bikes. Many of us like
going faster than 14 mph, myself included, and riding fast in a pack
of riders.
Don't break your arm patting yourself on the back. You're not
atypical here. You're about average.
charles ramsey
of their rims. If any shop or web site sells a mavic rim under the
mavic set price mavic will stop selling to them. There has been a
lawsuit over this.
Tim McNamara
> On Sat, 14 Feb 2004 08:29:26 GMT, Steve Knight
> <ste...@knight-toolworks.com> may have said:
>
>> I was tightening the spokes when I saw one that looked like it had
>>a hump around it. a closer look reveled that the rim was cracked
>>around the spoke and it was pulling out.
>
> This has been reported on a number of occasions, particularly with
> the Mavics that have the heavily anodized surfaces. There are some
> who feel that there is reason to believe that the anodization may be
> at least partially responsible for the failures. I'm not 100%
> convinced that the same rim, without the anodizing, wouldn't have
> the same failures, though perhaps not as quickly.
Fortunately for the purposes of discussion, Mavic provided us with
the data for this by producing the MA2 and the MA40- identical rims
except the latter was "hard anodized." The MA40 was well known for
cracking, the MA2 was not. Neither is a "stoopid lite" rim.
Tim McNamara
> diann...@NOSPAMyahoo.com wrote:
>
>> So one might ask: how many miles do you want before *your* rim
>> cracks?
>
> I don't want my rims to ever crack. I want to retire it when the
> sidewalls get too thin from brake pad wear. This didn't use to be
> such a high expectation.
Ditto. This is the appropriate expectation.
Benjamin Lewis
>> Then you have absolutely no basis to your claim that your Mavics are
>> "good rims" -- and you've even admitted that you destroy enough of your
>> wheels in crashes, so you have no way of knowing how well they'll hold
>> up for a more typical rider.
>
> Pray tell, define typical!
I merely meant that most people don't crash so often.
> Nothing except that when someone shouts "MAVIC RIMS SUCK" it gets my
> goat. You shout "Cannondale Sucks!" and I'd argue that one too. Yes, I
> agree that some of Mavic's rims suck. But categorically? That's like
> saying Bordeaux wine sucks, or...
All of Mavic's rims are anodized. No one has offered any convincing
evidence, to me at least, that anodization is beneficial in any way, and it
makes the rims cost more. With that in mind, even if the anodization
*doesn't* lead to early rim failures, I object to it.
--
Benjamin Lewis
Don't take life so serious, son, it ain't nohow permanent.
-- Walt Kelly
dianne_1234
wrote:
>dianne_1234 wrote:
>> So one might ask: how many miles do you want before *your* rim cracks?
>
>More than 800 miles. x517, spokes pulled through. That's pathetic.
>
>Definitely more than 200 miles. X517, split 8" along the spoke holes under
>the rim strip. That's really pathetic.
>
>Greg
Yeah, that's weak.
So how many miles do you want before *your* rim cracks?
dianne_1234
wrote:
>diann...@NOSPAMyahoo.com wrote:
>
>> So one might ask: how many miles do you want before *your* rim cracks?
>
>I don't want my rims to ever crack. I want to retire it when the sidewalls
>get too thin from brake pad wear. This didn't use to be such a high
>expectation.
Okay. How many miles do you want the rim to go before the side walls
wear too thin?
dianne_1234
wrote:
>diann...@NOSPAMyahoo.com wrote:
>
>> On Sat, 14 Feb 2004 21:39:07 -0800, Benjamin Lewis <bcl...@cs.sfu.ca>
>> wrote:
>>
>>> Mike S. wrote:
>>>
>>>> ?? 2 rims cracking at the eyelets in 18 years is low expectations?
>>>
>>> Yes. If you're rims don't either fail (if they fail) due to an accident
>>> or from brake pad wear, there's a problem with them.
>>
>> In my opinion, if rims fail only in those two modes ... then there is
>> excess weight in them.
>
>Anodizing does not make rims lighter.
Good point, thanks.
Whose rims aren't anodized?
Steve Knight
>Your bike shop's advice is, in my estimation, good. Their offer of a
>loaner is a stellar recommendation for them.
yep that was a good touch. down at my shop I have three other shops to choose
from this fellow is a little farther but worth it. he mostly sells used road
bikes on commission.
--
Knight-Toolworks & Custom Planes
Custom made wooden planes at reasonable prices
See http://www.knight-toolworks.com For prices and ordering instructions.
dianne_1234
>dianne_1234 wrote:
>> Interesting comment, thanks. I have a few questions:
>>
>> 1. How can I differentiate fatigue, SCC and extrusion defects with
>> ordinary observations tools?
>
>a magnifying glass 10x or better is readily available and good for
>looking at fracture surfaces.
Good idea, thanks.
>for fatigue, if you look at a "classic" fatigue fracture surface like a
>broken crank arm [one that has *not* had the two broken bits placed back
>together and ground around like folks do when they're in "look at this!"
>mode], you'll get two major zones on the fracture surface. one will be
>relatively smooth transgranular surface, typically with "beach marks",
>lines where the crack has grown minutely at each stress cycle and leaves
>a small striation. the other rough surface where the fatigue crack has
>grown sufficiently to start brittle fracture.
Not sure how "classic fatigue" might fit with rim cracks at spoke
holes. Unlike a crank, the stress in the rim *reduces* as the crack
grows (and the spoke decreases tension). So normally I wouldn't expect
to see the rim reach brittle fracture; just the beach mark portion.
Any comments?
>for SCC, it's harder because there are different types depending on the
>alloy system, but for rims, you'll often you'll get a granular fracture
>surface. note that the presence of visible corrosion on a fracture
>surface doesn't necessarily indicate it's the cause, just that it's
>corroded after cracking! you need a microscope for this one.
Okay.
>extrusion can be surmised from granular cracking along the extrusion
>axis, but needs metallography to be sure.
Maybe we're talking past each other here. I consider extrusions to be
basically "defective" compared to text book material properties, and
it's the job of the rim designer to test and iterate until the
extrusion's relatively poorer properties are addressed in the rim's
design.
In other words, thicken the wall or add support (double eyelets?)
until the poorer material properties of the extrusion are sufficient.
Or do you mean something different?
>> 2. Given that spoke tension puts the rim hole under stress even while
>> not riding, would you expect SCC to crack the rim even without any
>> riding?
>
>yes, but this is a compound problem. SCC + fatigue often work together.
> sometimes not. depends on the SCC system & the use.
I once saw a Wheelsmith Gold Label wheel built with an MA40 rim break
with zero miles. It had been hanging in the shop for less than a year
when we noticed several postage stamp sized sections of the spoke face
had separated as Jobst describes. Other than this one case, I know of
no others.
I think the MA40 was somehow especially cursed. Speculation: Maybe
Mavic was learning more than just hard anodizing at the time. Harsh
chemicals left in the rim, maybe?
>> 3. Extrusions are rarely solution heat-treated (I understand air or
>> water cooling is usually as good as it gets for bike rims). Would the
>> temper have anything to do with the various causes of cracking?
>
>yes, but it depends. extrusions such as aluminum frame tubes depend
>extensively on their heat treatments for their post-weld strength, 6061
>for example. 6061 frame tube alloys are similar to rim alloys from what
>i understand, so i would expect rims to be heat treated if their joint
>is welded, but not sufficiently to affect the grain structure inherited
>from its extrusion.
So is that a "no" (for 6061)?
I'd be shocked if any rim was heat treated after extruding. I can just
imagine the pretzel you'd get out of the oven! ;-)
Do you know of any?
>as a terminology aside, for aluminum alloys, it's usually aging, not
>tempering. the "solution" part is where the alloy is heated so that its
>hardening agents are in "solid solution". it's then quenched,
>essentially "freezing" these components in their dissolved state. then
>it's aged by reheating to a lower temperature which allows hardening
>particles to form from solution. it's like when olive oil goes cloudy
>in cold weather. this process may be repeated 2 or even 3 times at
>different temps depending on alloy to get the required properties.
>
>> 4. I've seen rims crack at the spoke holes in various directions:
>> Generally circumferentially, generally transversally, and radiating
>> from the hole in generally "all" directions. Do any of these seem to
>> be related to the various causes you mention (e.g., SCC, extrusion
>> defect, etc.)?
>
>if you have multiple cracks radiating around the hole in all directions,
>that's anodizing. generally, from what i've seen at any rate, actual
>metal cracking in a rim like this is pretty rare. [if you have any pics
>you could post, that would be great.]
Sorry, used to have one (a Mavic MTB rim) but can't find it now.
>the circumferential stuff is typically extrusion, with maybe a bit of
>SCC thrown in to start the ball rolling.
And usually use, by which I mean fatigue. Or not?
> i note that mavic 717's now
>have a plastic valve hole liner to stop dissimilar metal corrosion where
>the brass valve touches the alloy around the valve hole. a number of
>the rims i've seen that have cracked internally have started splitting
>at exactly this spot. i'm sure being kept wet for extended periods by
>absorbent cloth rim tape doesn't help.
>
>> 5. Does SCC failure require stress + time (to corrode)?
>
>yes. but time is a big variable. some agents/alloys will fail rapidly.
> others take ages.
>
>there are stress tests where a component has a small quantity of agent
>applied and it quickly falls apart as the stress and the agent work
>together. watching a residually stressed component like a cold drawn
>tube open up like a time-lapse movie of a flower opening is an
>impressive sight! there are reasons certain chemicals are not allowed
>on planes.
Thanks for the reply!
dianne_1234
<tim...@bitstream.net> wrote:
>Indeed, which is what makes anodizing rims all the more foolish.
What other finishes are available? I know polishing, but the exploded
Weinmann plant makes those hard to find.
dianne_1234
... after how many miles?
dianne_1234
wrote:
>All of Mavic's rims are anodized. No one has offered any convincing
>evidence, to me at least, that anodization is beneficial in any way,
Slows corrosion?
G.T.
For a mtn bike rim I want as many miles as it takes to wear through the
braking surface just like my first rims did.
G.T.
More than 200. What's your point? Considering that past rims that weighed
the same amount lasted more than 10 times as long your constant questioning
of how long we want our rims to last is getting ridiculous.
Tim McNamara
Well, polished, anodized, Alodine and various types of paint are the
options, I think. The Torelli Master (made for Torelli by Ambrosio)
is available polished, and ISTR someone pointing out to me that the
Sun CR18 is lso available polished.
Tim McNamara
Depends on how often you use your brakes, whether you ride in the wet
regularly, etc. Let's put it this way- in the 30+ years I've been a
bike nut, I've never worn out a sidewall on a rim. But I have always
lived in relatively flat to rolling areas (Chicago, Minnesota). I
hate riding in the rain so I avoid it. OTOH, Jobst has reported
wearing out sidewalls in a single 3 week tour in the Alps when it
rained nearly every day. He rides regularly in mountains, which I do
not, and thus has more opportunity to wear out rims. Several posters
to this newsgroup live in the Northwest of the US and also report
wearing out rims- if they didn't ride in the rain, they would ride
very rarely. Ditto the English, Scottish and Irish who have
discussed this in this newsgroup.
I sense that you want me to give some sort of absolute number, like
53,275.64 miles, that I consider to be acceptable before the rim fails
in some mode. I'm not going to do that. I will draw a distinction
between wearing out and material failure. Stuff wears out. Material
failure should be rare rather than frequent; unfortunately with
current rims on the market, we have the latter situation.
Tim McNamara
How many aluminum rims have you had rust out?
Tim McNamara
That's an unanswerable question, as I point out in another post. Why
are you continuing to ask it?
Sidewall wear is a consequence of local conditions and riding habits.
If you live in a flat, dry area you may not wear out a sidewall in
50,000 miles. If you live in Portland, Oregon and ride every day in
the mountains, you might chew through a couple of rims a year.
Mountain bikers will typically wear through a sidewall much faster
than road bikers.