Mavic X517 rims - cracking problems
Simon Ward
I have an aluminium framed hardtail MTB (Apollo) and carried about
25-30kg on the back.
I got Mavic X517s fitted before I left and during the course of the trip,
had to have the back rim replaced under warrantee 3 times. All three
started to crack either side of the spoke eyelets - the drive side being
worse. The first rim also started to split its internal box section
causing the rim to start spreading.
Mavic have not been able to give me any real explanation of whats causing
this, other than muttering about being laced too tight . However various
bike shops along the way have said the spoke tension seemed fine, could
detect nothing wrong with my setup, and said my overall load was within
acceptable limits.
Okay, I took dirt roads now and again, but the rim should be able to
handle that. Hell, its supposed to be a competion XC rim and besides, I
had taken no dirt roads prior to the first rim going belly up.
On the last replacement I upgraded to a Mavix D521 and haven't as yet
tested this under prolonged touring conditions, so time will tell.
Ray Green
>I got Mavic X517s fitted before I left and during the course of the trip,
>had to have the back rim replaced under warrantee 3 times. All three
>started to crack either side of the spoke eyelets - the drive side being
>worse. The first rim also started to split its internal box section
>causing the rim to start spreading.
My commuting bike had its rear X517 split. It went in the internal
section and split radially between two spoke drillings (the top one,
not the bottom eyeletted drilling) and I noticed the rim bulging.
Looking at other spoke holes I saw cracks propogating from them. This
was a silver X517 that had done 2000 miles on roads only. The tires
were road oriented i.e. narrower and pumped up a bit harder than
normal. Spoke tension was on the high side but within the capabilities
of the rim's static load but possibly overloaded from a fatigue point
of view which is worrying. I put another on but I'm sure the extrusion
has changed because the internal channel face seemed different
(couldn't directly compare since the old rim had been returned).
So my question is should this rim (and similar ones) be built with
lower tension at the expense of spokes comming loose. Or is there a
better XC rim that can be used without having to revert to slack,
glued nippled wheels.
W. Ray Green
Bard Brors
My Mavic 217 Ceramic rear wheel rim started cracking round the spoke holes
after about 3000 km. At 6000 km the sidewall split from brake wear. By then
the
cracks at the spoke holes were up to one cm long. I rebuilt the wheel using
DT
Revolution spokes instead of Competition in order to distribute the load
between
more spokes. It would probably be wise to use 36 spokes instestead of 32
for the rear wheel, but that requires a new hub.
Bard Brørs
Jobst Brandt
> So my question is should this rim (and similar ones) be built with
> lower tension at the expense of spokes coming loose. Or is there a
> better XC rim that can be used without having to revert to slack,
> glued nippled wheels.
You didn't say how much weight the wheel is carrying or how many and
what sort of spokes you have. I'm not familiar with this rim but my
guess is that it is probably anodized (not shiny silver in finish).
Anodizing is the best way to cause cracks in an otherwise ductile
metal like aluminum alloy. The other possibility is that the rim is
not a hollow section rim with steel sockets and eyelets to distribute
the load between inner and outer wall. Looser spokes will not help.
That only gives you a wheel in which the spokes will unscrew or the
whole thing wil collapse at some high stress event.
Don't buy colored rims. In fact, use Mavic MA-2 rims and forget all
this cracking.
Jobst Brandt <jbr...@hpl.hp.com>
Ray Green
>Ray Green writes:
>
>> So my question is should this rim (and similar ones) be built with
>> lower tension at the expense of spokes coming loose. Or is there a
>> better XC rim that can be used without having to revert to slack,
>> glued nippled wheels.
>You didn't say how much weight the wheel is carrying or how many and
>what sort of spokes you have. I'm not familiar with this rim but my
>guess is that it is probably anodized (not shiny silver in finish).
The X517 is a current lighweight Mavic mtb rim in various finishes
including hard anodized but my example was silver anodized which I
assumed to be for cosmetic purposes only without any of the known
problems from hard anodizing. I weigh 180lbs the rear wheel has 32
spokes - DT Competition. Most mtb rims nowadays are single eyelet,
hollow section.
The original poster referred to 'mumblings from Mavic' about too tight
spokes. I've heard mumblings in the n.g. too. So if modern rims aren't
what they were used to be then some compensation in the building
technique may be required to prolong their life. I'm just not sure
where the balance lies.
I've often thought that the point contact of the angular faced seat of
the nipple in the eyelet gives a load concentration. Some nipples I've
seen have a spherical seat (like a ball joint) that sits better in the
eyelet and wonder if this would alleviate any problems by better
distributing the spoke load.
Ray Green
Jobst Brandt
>> You didn't say how much weight the wheel is carrying or how many and
>> what sort of spokes you have. I'm not familiar with this rim but my
>> guess is that it is probably anodized (not shiny silver in finish).
> The X517 is a current lightweight Mavic MTB rim in various finishes
> including hard anodized but my example was silver anodized which I
> assumed to be for cosmetic purposes only without any of the known
> problems from hard anodizing.
All but the lightest trace of colored anodizing has the cracking
effect. The coating on silver anodizing is more than a trace. Why do
people buy this crap? Polished aluminum is a beautiful finish in
itself. Coating it with a hard, porous, brittle oxide severely
diminishes its strength.
> I weigh 180lbs the rear wheel has 32 spokes - DT Competition.
Good spokes but I would get some uncoated rims and preferably 36
spokes. You aren't doing yourself any favors with this stuff. I ride
road wheels on the roughest trails and have not had any cracking with
wheels that go 20000mi or until they wear down to 0.5mm on the braking
surface.
> Most MTB rims nowadays are single eyelet, hollow section.
That's not a good idea, considering that one can do better, especially
with a double walled rim that isn't using sockets and eyelets.
> The original poster referred to 'mumblings from Mavic' about too tight
> spokes. I've heard mumblings in the n.g. too. So if modern rims aren't
> what they were used to be then some compensation in the building
> technique may be required to prolong their life. I'm just not sure
> where the balance lies.
It's the varying load that counts primarily. If your spokes aren't
tight enough the wheel will be weak. The cyclic load of the rider
on the does not change with spoke tension
> I've often thought that the point contact of the angular faced seat
> of the nipple in the eyelet gives a load concentration. Some nipples
> I've seen have a spherical seat (like a ball joint) that sits better
> in the eyelet and wonder if this would alleviate any problems by
> better distributing the spoke load.
Conventional spoke nipples are conical under the head to allow a
slight angle and for strength. The main thing is to not get large
flange hubs that create too large an angle at the rim.
Jobst Brandt <jbr...@hpl.hp.com>
u...@ubcbike.com
around the eyelets. The nice thing about it is they do not hassle you about
it usually they warranty it with no problem. They make some really cool rims
but the fact that they crack so easily we are no longer carrying them in our
store. If you need any help contacting Mavic or any other technical issues
please feel free to call or email.
Thanks,
Carlos Mirabal
University Bicycle Center
1220 E. Fletcher Ave.
Tampa, Fl. 33612
(813) 971-2277
u...@ubcbike.com
www.ubcbike.com
In article <72ggu6$e5h$1...@corolla.OntheNet.com.au>,
Simon Ward <s...@trendsetting.com.au> wrote:
> I've recently completed a Perth to Gold Coast ride - about 7600km.
> I have an aluminium framed hardtail MTB (Apollo) and carried about
> 25-30kg on the back.
>
> I got Mavic X517s fitted before I left and during the course of the trip,
> had to have the back rim replaced under warrantee 3 times. All three
> started to crack either side of the spoke eyelets - the drive side being
> worse. The first rim also started to split its internal box section
> causing the rim to start spreading.
>
> Mavic have not been able to give me any real explanation of whats causing
> this, other than muttering about being laced too tight . However various
> bike shops along the way have said the spoke tension seemed fine, could
> detect nothing wrong with my setup, and said my overall load was within
> acceptable limits.
>
> Okay, I took dirt roads now and again, but the rim should be able to
> handle that. Hell, its supposed to be a competion XC rim and besides, I
> had taken no dirt roads prior to the first rim going belly up.
>
> On the last replacement I upgraded to a Mavix D521 and haven't as yet
> tested this under prolonged touring conditions, so time will tell.
>
-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Tim McNamara
>I have first hand knowledge about all Mavic rims...they all have problems
>around the eyelets. The nice thing about it is they do not hassle you about
>it usually they warranty it with no problem. They make some really cool rims
>but the fact that they crack so easily we are no longer carrying them in our
>store.
What's "really cool" about rims that are basically guaranteed to break? I
just lost a pair of Mavic 220's- which I bought as a wheelset via mail
order from Colorado Cyclist thinking that "silver" finished meant polished
aluminum rather than silver anodized (buying the built wheels was
significantly cheaper than buying the constituent parts). The front rim
is bulging or molehilling at every ferrule and the rear has outright
failed with cracks at at least 10 ferrules, including one large failure
about 1 cm long.
As I've said before- never again will I buy anodized rims. This is the
second set to fail on me (the first was a pair of dark anodized Sun road
rims).
It's peculiar- rim weights have skyrocketed in the past decade, now
weighing as much as double as rims of 20 years ago... yet the rims fail
faster than ever. I have a pair of Rigida 13-20 clinchers which I built
up in 1978- they're still fine. OTOH, my Mavic 220's were about a year
old and had seen about 2,000 road miles and 25 off-road miles. My Sun
road rims were about 2 years old and probably had about the same mileage
on them. I thought technology was supposed to *advance.*
--
The heart has its seasons, its evenings
and songs of its own.
-Robert Hunter
Matt O'Toole
Jobst Brandt wrote in message <72ihff$jlp$2...@hplms2.hpl.hp.com>...
>All but the lightest trace of colored anodizing has the cracking
>effect. The coating on silver anodizing is more than a trace. Why do
>people buy this crap? Polished aluminum is a beautiful finish in
>itself. Coating it with a hard, porous, brittle oxide severely
>diminishes its strength.
The only reason many people buy this crap is that it's the only thing being
sold. A lot of us do know better, and we search far and wide for what we
know is best. I can't think of a single MTB rim available today that isn't
anodized. Even if there was one, it's likely the local shop would balk at
ordering it, because he wants to sell the pile of Mavics he's invested in
first.
What we need is some brave soul to think for himself, take the initiative,
and offer a non-anodized rim. He could hype the hell out of its superior
fatigue resistance, and use that as the main marketing angle. He could slam
Mavic for all their rim failures, and their ridiculously high prices;
pointing out the increased overhead they have with their four color, full
page ads, and those cute little rim section displays they put in all the
bike shops.
Matt O.
Mark McMaster
E Harp
<ma...@deltanet.com> wrote:
> Matt O.
That is what my experience has been: there never seemed to be any question
about using anodized rims when I had my last two wheelsets made up; one by
an LBS and one mail order.
I have been riding seriously for over two years now, and I have destroyed
four wheels. But, none of them failed because of anything other than
abusive use on my part.
I regularly ride on a pair of Mavic D521s that are "hard anodized." They
have about 1,500 road and offroad miles on them at this point. I took the
opportunity to give them a good look over when changes tires this week and
find nothing wrong with them. Granted, 521s are oversized rims meant for
downhill use.
I also have a pair of Mavic 221 OEM wheels that have seen about 600 to 800
miles of mostly commuting use. No eyelets, and I think silver anodizing.
They are fine as well.
Could there be other issues at work here? I know I put more than average
stress on my wheels, yet spokes seem to fail long before the rims do
(though I do dent and bend them now and again).
I guess I find it hard to believe that manufacturers, with all their
faults, would push so many anodized wheels if they have such fatal flaws.
Could it be the result of the expected short life of racing gear? Is it
possible that they have improved the process over the years?
Ed Harp
San Jose, CA
Dan Webster
Lite is an EXCELLENT rim..not anodized....it has a double box construction,
with eyelets! Crypes, what are you on? And why do people think you are the
god of this group!
Dan
E Harp wrote in message ...
Jacob Høgh Olesen
> All but the lightest trace of colored anodizing has the cracking
> effect.
There is something I don't undersetand here - almost all aluminium climbing
hardware is anodized - often hard anodized. Failure can be fatal, so you
definately won't like to make it failure prone. Climbing gear gets knocked
around all the time and from time to time takes some really high chock
loads, often close to breaking strength. If anodizing is asking for trouble,
then why use it in these applications? I guess lawsuits would pile up as the
bodies would. Is there more to the story than that? Is there some difference
between climbing and bicycling equipment that affects the usability of
anodizing? I'd surely like to know if my 'biners and stuff are going to fail
suddenly or what
Regards Jacob H. Olesen
andrew s mein
Umm, MA2? Bright-dipped non-ano finish road rim? Made by Mavic?
Hmm...
Drew
Matt O'Toole
Mark McMaster wrote in message <364E62...@ix.netcom.com>...
>Most of the Bontrager rims are offered in a brushed finish.
That's what I thought, too, but the lying thieves in the bike shops deny
their existence.
Matt O.
Matt O'Toole
andrew s mein wrote in message
<72ni8a$6kro$1...@newssvr04-int.news.prodigy.com>...
> Umm, MA2? Bright-dipped non-ano finish road rim? Made by Mavic?
>Hmm...
Umm, not sold by any shop around here? Its existence flatly denied by said
shops, who would rather sell one of the newer, $60 apiece, anodized models?
Plus, I'm looking for MTB rims...
Matt O.
Matt O'Toole
E Harp wrote in message ...
>That is what my experience has been: there never seemed to be any question
>about using anodized rims when I had my last two wheelsets made up; one by
>an LBS and one mail order.
>I have been riding seriously for over two years now, and I have destroyed
>four wheels. But, none of them failed because of anything other than
>abusive use on my part.
>
>I regularly ride on a pair of Mavic D521s that are "hard anodized." They
>have about 1,500 road and offroad miles on them at this point. I took the
>opportunity to give them a good look over when changes tires this week and
>find nothing wrong with them. Granted, 521s are oversized rims meant for
>downhill use.
>
>I also have a pair of Mavic 221 OEM wheels that have seen about 600 to 800
>miles of mostly commuting use. No eyelets, and I think silver anodizing.
>They are fine as well.
>
>Could there be other issues at work here? I know I put more than average
>stress on my wheels, yet spokes seem to fail long before the rims do
>(though I do dent and bend them now and again).
If the spokes are failing, your wheels are not well built. Of course, the
exceptiuon to that would be if you get branches caught in your wheels, as I
do occasionally.
You're not stressing your wheels highly, at least in a fatigue sense.
Fatigue problems come from many, many load cycles from pedaling. Jobst has
mentioned that he gets 20,000 miles from a pair of non-anodized rims, while
I hear stories of anodized rims failing within 10% of that figure. That's a
big difference.
I've only had one pair of rims crack at the spoke holes. They were hard
anodized. by that time, they were due for replacement because of worn
sidewalls, but it was the anodizing that caused the cracking.
>I guess I find it hard to believe that manufacturers, with all their
>faults, would push so many anodized wheels if they have such fatal flaws.
>Could it be the result of the expected short life of racing gear?
MTB rims often wear out from braking before they develop cracks. Also, the
average MTB rim probably sees less service than the average road bike rim.
Still there's no excuse for taking a perfecy good design, and reducing its
potential service life by a factor of 10, just for the sake of cosmetics.
>Is it
>possible that they have improved the process over the years?
No. Anodizing is anodizing is anodizing. That dark brown, hard anodizing
is a lot worse, though.
Jobst briefly mentioned nitriding in his book. This would be fine, if you
like the gold color. It was used a lot on sailboat hardware back in the 60s
and 70s, because it offered some corrosion protection in a harsh seawater
environment, *without embrittling the surface of the metal* as anodizing
does. As anodizing became more widely available and cheaper throughout the
70s and 80s, it became trendy to have black anodized parts on racing
sailboats. It was cheaper and easier than painting them, and the finish
didn't chip or scratch as easily when banged on decks and other rigging.
This was followed by a wave of broken booms and spinnaker poles. The
geniuses behind these products started making them thicker, until they
realized that strength wasn't the issue. They noticed the older,
non-anodized, lighter guage parts were still holding up to heinous winds,
while the newer, anodized ones would break after a couple of years, even if
they'd never seen a strong breeze. The taffy-like, stretched and torn
breaks on the non-anodized parts, vs. the clean cracks on the anodized ones,
told the whole story. Fatigue was the problem, and the pretty black
anodizing was the culprit.
Matt O.
Mark McMaster
Well, in addition to some of the older BCX-2 and Red Label and Blue
Label rims that I have that are all in a brushed finish, I've got some
Mustang Asyms that are completely un-anodized. The sidewalls of the
Mustangs are machined (which I don't particularly feel is necessary),
but the bottom walls are completely unfinished. I picked them up for
somewhere between $35 and $40 each.
Mark McMaster
MMc...@ix.netcom.com
Matt O'Toole
rich...@cruzio.com wrote in message <72obm6$jom$1...@nnrp1.dejanews.com>...
>They don't sell well. Customers prefer anodized rims.
Well, if you find yourself with a pile 'o' plain ones you can't get rid of,
send a few to me! ;-)
BTW, are those actual customers you're talking about, or
manufacturers/dealers, shopping for bullet points?
Cheers,
Matt O.
E Harp
<ma...@deltanet.com> wrote:
> >Could there be other issues at work here? I know I put more than average
> >stress on my wheels, yet spokes seem to fail long before the rims do
> >(though I do dent and bend them now and again).
>
> If the spokes are failing, your wheels are not well built. Of course, the
> exceptiuon to that would be if you get branches caught in your wheels, as I
> do occasionally.
Spoke failures were all the result of similar cirsumstances, including
hitting jagged rocks sideways, coming off of tall curbs too close to the
curb, etc.
> You're not stressing your wheels highly, at least in a fatigue sense.
> Fatigue problems come from many, many load cycles from pedaling. Jobst has
> mentioned that he gets 20,000 miles from a pair of non-anodized rims, while
> I hear stories of anodized rims failing within 10% of that figure. That's a
> big difference.
>
> I've only had one pair of rims crack at the spoke holes. They were hard
> anodized. by that time, they were due for replacement because of worn
> sidewalls, but it was the anodizing that caused the cracking.
True. I'll be proud to say I have gone 20,000 miles on all of my bikes
combined, let alone on a single pair or rims. I'm working on it. : )
> >Is it
> >possible that they have improved the process over the years?
>
>
> No. Anodizing is anodizing is anodizing. That dark brown, hard anodizing
> is a lot worse, though.
>
> Jobst briefly mentioned nitriding in his book. This would be fine, if you
> like the gold color. It was used a lot on sailboat hardware back in the 60s
> and 70s, because it offered some corrosion protection in a harsh seawater
> environment, *without embrittling the surface of the metal* as anodizing
> does. As anodizing became more widely available and cheaper throughout the
> 70s and 80s, it became trendy to have black anodized parts on racing
> sailboats. It was cheaper and easier than painting them, and the finish
> didn't chip or scratch as easily when banged on decks and other rigging.
>
> This was followed by a wave of broken booms and spinnaker poles. The
> geniuses behind these products started making them thicker, until they
> realized that strength wasn't the issue. They noticed the older,
> non-anodized, lighter guage parts were still holding up to heinous winds,
> while the newer, anodized ones would break after a couple of years, even if
> they'd never seen a strong breeze. The taffy-like, stretched and torn
> breaks on the non-anodized parts, vs. the clean cracks on the anodized ones,
> told the whole story. Fatigue was the problem, and the pretty black
> anodizing was the culprit.
>
> Matt O.
Well, all I can say is that I will forgo anodized rims next trip. Does
anyone make a heavier 700 mm rim (say, for touring) that is not anodized?
The MA 40?
rich...@cruzio.com
MMc...@ix.netcom.com wrote:
> > >people buy this crap? Polished aluminum is a beautiful finish in
> > >itself. Coating it with a hard, porous, brittle oxide severely
> > >diminishes its strength.
> >
> > The only reason many people buy this crap is that it's the only thing being
> > sold. A lot of us do know better, and we search far and wide for what we
> > know is best. I can't think of a single MTB rim available today that isn't
> > anodized. Even if there was one, it's likely the local shop would balk at
> > ordering it, because he wants to sell the pile of Mavics he's invested in
> > first.
> >
> > and offer a non-anodized rim. He could hype the hell out of its superior
> > fatigue resistance, and use that as the main marketing angle. He could slam
> > Mavic for all their rim failures, and their ridiculously high prices;
> > pointing out the increased overhead they have with their four color, full
> > page ads, and those cute little rim section displays they put in all the
> > bike shops.
>
>
> MMc...@ix.netcom.com
>
They don't sell well. Customers prefer anodized rims.
;-)
KB
Simon Ward
distance tourers had with their rims and the solution they had found, as
reliability is paramount over rim weight or any other consideration.
It seems like the near A$100 I spent upgrading to the D521 was a waste of
time as it is hard-anodized. I could go on making warrantee claims
ad-nauseam but I would rather the dependability. As it is, the warrantee
claims I have made prolonged my journey by about two weeks and forced me
to pay for accommodation and long distance phone calls when I'd preferred
not to.
One of the main reasons for this cross-Australia trek was as a shakedown
and fact-finding ride in preparation for riding the length of South
America from south to north.
So what is recommended so as I don't find myself stuck in a remote
Bolvian town trying to organise a replacement from a bike shop in La Paz?
Matt O'Toole
E Harp wrote in message ...
>Well, all I can say is that I will forgo anodized rims next trip. Does
>anyone make a heavier 700 mm rim (say, for touring) that is not anodized?
>The MA 40?
There's the venerable MA2, which is still avilable, although not anywhere
near where I live. I have seen it lately in the Nashbar catalog, and maybe
the Performance catalog, too.
Matt O.
John Stevenson
Simon Ward <s...@trendsetting.com.au> wrote:
[posted and mailed]
>So what is recommended so as I don't find myself stuck in a remote
>Bolvian town trying to organise a replacement from a bike shop in La Paz?
On the basis of what has been discussed so far, you need some heavy,
non-anodised rims. I believe the following are available in that
configuration, though you will probably end up having to force a bike shop
to special order them for you:
Sun Rhyno Lite
Bontrager Mustang
The Sun importer for Australia is Bike Corp in Melbourne (1800 810155);
Bontrager is handled by Trek Bicycles Australia in Sydney (02 9299 7444).
Also, I believe Velocity (07 3289 9262) do non-anodised rims. Since they
are an Australian company it should be very easy to order such rims even if
they are not a stock item. Their Aero Heat Deep V is intended for downhill
mountain bike racing, weighs a shade under 600g and is tough as old boots,
mostly by dint of the sheer quantity of metal there.
cheers
john
--
john...@magna.com.au
Writer, editor, escaped wage slave
Owner of the MTB-OZ mailing list, Australia's on-line MTB community
andrew s mein
I believe (obviously I cannot know, as Mr. Ward's wheel is not here for my
inspection) Mr. Ward's problem does not come from the anodized surface
treatment of his rims, but from the construction of the rim. First, I
would like to note that Mr.Ward is putting quite a load on his rear wheel-
50-60lbs of dead weight on the frame (weight that cannot be unloaded over
rough stuff) will put a great deal more stress on equipment than an unloaded
bike.
Mavic's 517 is a cross country racing rim, and certainly not one I would
choose for a transcontinental tour, for a couple of reasons- 1) it is light
(claimed weight of 395g); 2) it is a single eyeletted rim- the eyelets in
the rim place the spoke loads into only the outside wall, not the inner one
as well (this has a great deal of bearing on spoke-hole cracking
particularly in a light rim with not much material in the spoke bed).
For their intended application, 517s are great rims. However, as a big
fella, I would have a bit of trepidation running them in a low maintenance
situaution for myself. Whoever suggested to Mr.Ward that these would be
great touring rims was misinformed. The D521s, however, are great rims for
this application- very burly (695g), with lots of material in the spoke bed.
Lastly, a note on anodizing. Anodizing is the application of electric
current to a piece of metal in an electrolyte bath which produces a layer of
hydrated aluminium oxide (boamite) on the surface of the aluminium. This
oxide layer is much harder than the parent metal, and, until sealing, is
porous (thus, coloured anodizing- the boamite soaks up the dye). Colored
anodizing is only 2-3 microns thick, but hard anodizing is much thicker-
10-12 microns. It is much more durable, but cannot be made to take pretty
colours (thus the brownish/grey colour of hard ano rims).
In bicycle rims, anodizing has a couple of advantages, and one big
disadvantage. One advantage is cosmetic- it keeps the rim from getting
stained by brake pad residues and aluminium oxides from the braking surface,
and other poopy stuff. It also adds strength to the rim- think of sticking
a piece of paper card to the outside of modeling clay (this really only goes
for hard ano coats, and even then the affect isn't large). The big
disadvantage is that anodizing is much more slippery than bare aluminium,
and good braking can be hard to achieve until the ano in worn away (WTB
makes some abrasive brake pads which do a good job of this, and many rim
manufacturers now sand or machine the ano coat off of the rim sidewalls).
In closing, please bear in mind that anodizing has a very minor affect
on rim strength, and its chief disadvantage is cost. Mr. Ward should be
more concerned with appropriate equipment choice and wheel build quality
than thin surface treatments.
(steps down from the soapbox)
Drew
-
Simon Ward wrote in message <72obia$j45$1...@corolla.OntheNet.com.au>...
>I made the original post, in part, to find out what other problems long
>distance tourers had with their rims and the solution they had found, as
>reliability is paramount over rim weight or any other consideration.
>It seems like the near A$100 I spent upgrading to the D521 was a waste of
>time as it is hard-anodized. I could go on making warrantee claims
>ad-nauseam but I would rather the dependability. As it is, the warrantee
>claims I have made prolonged my journey by about two weeks and forced me
>to pay for accommodation and long distance phone calls when I'd preferred
>not to.
>
>One of the main reasons for this cross-Australia trek was as a shakedown
>and fact-finding ride in preparation for riding the length of South
>America from south to north.
Mark McMaster
>
> Well, all I can say is that I will forgo anodized rims next trip. Does
> anyone make a heavier 700 mm rim (say, for touring) that is not anodized?
> The MA 40?
The Mavic MA-2 is the same as the MA-40 without the hard-anodize. It
also costs less. The tough part is finding a retailler who stocks the
MA-2 - although there are several mail-order houses who have them
(Nashbar, Excel, etc.).
Mark McMaster
MMc...@ix.netcom.com
tku...@diabloresearch.com
rich...@cruzio.com wrote:
> In article <364E62...@ix.netcom.com>,
> MMc...@ix.netcom.com wrote:
> >
> > Most of the Bontrager rims are offered in a brushed finish.
> >
That may be true Keith, but a lot of it is what's available. Most shops
carry the more expensive rims. Most manufacturers (dare we say Trek?)
build bikes with the more expensive parts. In most cases this is good
because the more expensive parts are generally superior in some way.
But not in the case of anodized rims.
By the way, I finally got a look at the Mavic rims that I said were
peeling off in layers. That wasn't quite accurate. What happened to
the rims was that fairly large sections came off in sheets. It looked
like gouging on the rims except the color of the metal in the gouges
was the same anodized grey as the rest of the times. I can't think of
how that could have occured unless the extruder was pushing a hell of
a lot of slush through with the aluminum. This could form pockets of
metal that were shoved into the surface but weren't part of it. The
anodizing operated between the two layers and when the surface was
abraded with the brake pads these just chunked out.
I would have thought that the lathe turning on the sidewalls would have
broken it free since it must be oxide and hard. The owner of the LeMond
that they are on said that for a long time, every couple of days the
brakes would start making noise and he'd pull the wheel off and clean
strips of aluminum out of the brake pads. The edges would be sharp and
stick the pieces into the pads.
tku...@diabloresearch.com
The Sun rim is very heavy and quite reliable. It would be hard to think of
a way that they rim could be hurt on even a heavy touring bike.
> Also, I believe Velocity (07 3289 9262) do non-anodised rims. Since they
> are an Australian company it should be very easy to order such rims even if
> they are not a stock item. Their Aero Heat Deep V is intended for downhill
> mountain bike racing, weighs a shade under 600g and is tough as old boots,
> mostly by dint of the sheer quantity of metal there.
Do not mistake rigidity for reliability. In fact, deep-V rims are very
strong but are not as reliable as box section rims because the V's are
so rigid that they dent instead of flexing out of the way and back again.
I think that Velocity offers several box section rims that ought to solve
the problem however.
Ray Green
>They don't sell well. Customers prefer anodized rims.
Go and re-roll some MA2's like you used to do, pity you used the MA40,
if you'd have selected the MA2 then perhaps history would have turned
out different. Get an apprentice on the job, you'd sell plenty to
readers of this n.g.
Ray
Alex Rodriguez
>> Most of the Bontrager rims are offered in a brushed finish.
>They don't sell well. Customers prefer anodized rims.
So does that mean you are going to stop making them or just that you don't
make that many?
---------------
Alex __O
_-\<,_
(_)/ (_)
Jobst Brandt
>> All but the lightest trace of colored anodizing has the cracking
>> effect. The coating on silver anodizing is more than a trace. Why
>> do people buy this crap? Polished aluminum is a beautiful finish
>> in itself. Coating it with a hard, porous, brittle oxide severely
>> diminishes its strength.
> The only reason many people buy this crap is that it's the only
> thing being sold. A lot of us do know better, and we search far and
> wide for what we know is best.
So what do you tell your dealer and what does he say to the supplier?
I get the impression that most people like to pay more than twice as
much for rims, so long as they are esoteric, having non metallic
finish and worthless expensive machined sides. I have overheard the
exchanges between customer and sales clerk that support that.
> I can't think of a single MTB rim available today that isn't
> anodized. Even if there was one, it's likely the local shop would
> balk at ordering it, because he wants to sell the pile of Mavics
> he's invested in first.
They make rims that sell and ones that make the most money. The world
is full of bicycle owners who seldom ride and they spend much money on
equipment to reinforce the idea that they are "into bikes". As I have
mentioned often, the whole crowd is a disaster for those of us who
like to ride on reliable equipment.
> What we need is some brave soul to think for himself, take the
> initiative, and offer a non-anodized rim. He could hype the hell
> out of its superior fatigue resistance, and use that as the main
> marketing angle. He could slam Mavic for all their rim failures,
> and their ridiculously high prices; pointing out the increased
> overhead they have with their four color, full page ads, and those
> cute little rim section displays they put in all the bike shops.
My bike shop carries MA-2 rims that I have used with good success
since the day that they were sold as the "Gentleman" label by Super
Champion.
Jobst Brandt <jbr...@hpl.hp.com>
Jobst Brandt
> Could there be other issues at work here? I know I put more than
> average stress on my wheels, yet spokes seem to fail long before the
> rims do (though I do dent and bend them now and again).
Build your own wheels and stop letting the bike shop sell you poorly
built ones.
> I guess I find it hard to believe that manufacturers, with all their
> faults, would push so many anodized wheels if they have such fatal
> flaws. Could it be the result of the expected short life of racing
> gear? Is it possible that they have improved the process over the
> years?
You are assuming the manufacturer is playing it straight, a belief
that is less warranted than believing that hard anodizing is a brittle
inelastic crust on an otherwise ductile material. I suppose you have
never had a scab from road-rash that cracked and bled because it was a
brittle hard crust over skin that normally stretches easily without
failure. There is a parallel. However, if you could check the
literature on the effects of anodizing on structural aluminum, where
you would discover the aircraft industry is well aware of these hazards.
Jobst Brandt <jbr...@hpl.hp.com>
Jobst Brandt
> Most of the Bontrager rims are offered in a brushed finish.
Polished would be better because it has less crack initiating detail
in the surface. For this reason, highly stressed machine parts are
often polished even though they are no visible for anyone to
appreciate the shine. A brush finsh is a field of tiny scratches.
Jobst Brandt <jbr...@hpl.hp.com>
rich...@cruzio.com
> > In article <364E62...@ix.netcom.com>,
> > MMc...@ix.netcom.com wrote:
> > >
> > >
>
> carry the more expensive rims. Most manufacturers (dare we say Trek?)
> build bikes with the more expensive parts. In most cases this is good
> because the more expensive parts are generally superior in some way.
> But not in the case of anodized rims.
It may be that the dealers have a perception of what customers want
and then stock that. We have had them in stock for some time and they
are not selling well. When we anodize them they sell.
By the way, there are significant differences in the fatigie performance
of aluminum rims that are hard anodized and decoratively anodized. It is
not the case that the decirative anodizing compromises fatigue strength
around the eyelets.
The differences in coating thickness and rigidity (of the coating
section, not just the material that makes up the coating itself)
affectthe base metal in different ways. The thicker, dark hard
anodizing cracks in larger pieces, and it's rigidity makes the
area at the crack a significant stress riser. The decorative
coating is much thinner and, while it is also very brittle, it
breaks into much smaller regions and the stress intensity at
any one crack is much closer to the normal stress in the base metal.
We have checked this out.
All aluminums fail in fatigue, and hard anodizing can promote those
failures. There are also many design variables and manufacturing
process variables that influence this behavior. It is not simply
a matter of the coating.
Polished aluminum might be slightly better than a decoratively
anodized rim in that regard, though it is not likely to be a big
difference. Shot peened aluminum would be the best. Brushed
aluminum is probably not as good as polishing or anodizing the
aluminum because of the tendency to smear aluminum at the abraded
surface. The change in tensile residual stress at the edge of the
hole in the rim, in a microscopic gouge from the abrasive process,
can set off a crack. This is a theoretical discussion of course.
We can't measure any difference in testing and don't see many come
back from that cause.
> By the way, I finally got a look at the Mavic rims that I said were
> peeling off in layers. That wasn't quite accurate. What happened to
> the rims was that fairly large sections came off in sheets. It looked
> like gouging on the rims except the color of the metal in the gouges
> was the same anodized grey as the rest of the times. I can't think of
> how that could have occured unless the extruder was pushing a hell of
> a lot of slush through with the aluminum. This could form pockets of
> metal that were shoved into the surface but weren't part of it. The
> anodizing operated between the two layers and when the surface was
> abraded with the brake pads these just chunked out.
>
> I would have thought that the lathe turning on the sidewalls would have
> broken it free since it must be oxide and hard. The owner of the LeMond
> that they are on said that for a long time, every couple of days the
> brakes would start making noise and he'd pull the wheel off and clean
> strips of aluminum out of the brake pads. The edges would be sharp and
> stick the pieces into the pads.
>
> -----------== Posted via Deja News, The Discussion Network ==----------
> http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Sounds like a topic for the journal of irreproducable results (there is such
a thing and we used to ammuse ourselves looking at it when I was in school -
remarkable analogs to life in there...).
KB
rich...@cruzio.com
ad...@columbia.edu (Alex Rodriguez) wrote:
> In article <72obm6$jom$1...@nnrp1.dejanews.com>, rich...@cruzio.com says...
>
> >> Most of the Bontrager rims are offered in a brushed finish.
>
> >They don't sell well. Customers prefer anodized rims.
>
> make that many?
> ---------------
> Alex __O
> _-\<,_
> (_)/ (_)
>
>
Dunno for sure. We use them on less expensive bikes because it is a way to
give a little more rim for the money. My guess is that they will be available
because of that, but only the rim sections and drillings we typically use
for those bikes, which wouldn't be the ones most people want for trick
wheels.
rich...@cruzio.com
wray...@hotmail.com (Ray Green) wrote:
> if you'd have selected the MA2 then perhaps history would have turned
> out different. Get an apprentice on the job, you'd sell plenty to
> readers of this n.g.
>
> Ray
>
We made a lot of MTB rims out of MA2s.
History would have been the same either way. mavic learned that light
weight MTB rims were a good think and cranked it up. I would have been
in the way no matter what.
I'm evening it out if you have a long view of things. I haven't
forgotten...
No hard feelings of course. I learned a lot and got a start in
the rim design biz. They always treated me fair. More than fair
in fact.
No way am I hand rolling rims again, and readers of this group do
not want any. I promise...
;-)
Jobst Brandt
> They don't sell well. Customers prefer anodized rims.
Customers don't know what they want, they make up their minds on the
pitch they get from the sales clerk and their friends, who have also
been nursed on the same sales pitch. How long have we read hard
anodized is stronger. Harder must be stringer in most peoples
estimation. The problem is that a gullible public is driving the
industry instead of racing teams whose buyers used to decide what got
used. That was before fitness became a popular pursuit, or at least
the perception of fitness.
Jobst Brandt <jbr...@hpl.hp.com>
Jobst Brandt
> There's the venerable MA2, which is still avilable, although not
> anywhere near where I live. I have seen it lately in the Nashbar
> catalog, and maybe the Performance catalog, too.
Your bike shop can order them any time. If they don't have them then,
they are not interested in you and the problem but more on selling
expensive rims.
Jobst Brandt <jbr...@hpl.hp.com>
Jobst Brandt
>> All but the lightest trace of colored anodizing has the cracking
>> effect.
> There is something I don't understand here - almost all aluminium
> climbing hardware is anodized - often hard anodized. Failure can be
> fatal, so you definitely won't like to make it failure prone.
> Climbing gear gets knocked around all the time and from time to time
> takes some really high chock loads, often close to breaking
> strength.
How many million stress cycles do you expect to get on these
carabiners? A bicycle wheel gets about eight million stress cycles per
thousand miles.
> If anodizing is asking for trouble, then why use it in these
> applications? I guess lawsuits would pile up as the bodies would. Is
> there more to the story than that? Is there some difference between
> climbing and bicycling equipment that affects the usability of
> anodizing? I'd surely like to know if my 'biners and stuff are going
> to fail suddenly or what
In this application, hard anodizing is a wear surface and prevents
metal from being worn off as a rope slides through the loop. I think
the climbing equipment has it right.
Jobst Brandt <jbr...@hpl.hp.com>
Eric Salathe
> Don't buy colored rims. In fact, use Mavic MA-2 rims and forget all
> this cracking.
and:
> All but the lightest trace of colored anodizing has the cracking
> effect. The coating on silver anodizing is more than a trace. Why do
> people buy this crap? Polished aluminum is a beautiful finish in
> itself.
So what is that shiny coating on MA-2s if not clear anodizing? Or on any
shiny bike part? It's certainly not polished aluminum.
Eric Salathe
Seattle WA
Jobst Brandt
> They don't sell well. Customers prefer anodized rims.
Customers don't know what they want, they make up their minds on the
pitch they get from the sales clerk and their friends, who have also
been nursed on the same sales pitch. How long have we read hard
anodized is stronger. Harder must be stronger in most peoples
Jobst Brandt
>> All but the lightest trace of colored anodizing has the cracking
>> effect. The coating on silver anodizing is more than a trace. Why
>> do people buy this crap? Polished aluminum is a beautiful finish
>> in itself.
> So what is that shiny coating on MA-2s if not clear anodizing? Or on
> any shiny bike part? It's certainly not polished aluminum.
It IS polished aluminum. It may have a clear coat over it or even a
clear alodine treatment, neither of which is hard and brittle.
Jobst Brandt <jbr...@hpl.hp.com>
ceck...@aol.com
<sal...@atmos.washington.edu> wrote:
> Jobst Brandt wrote:
> > Don't buy colored rims. In fact, use Mavic MA-2 rims and forget all
> > this cracking.
>
> and:
> > All but the lightest trace of colored anodizing has the cracking
> > effect. The coating on silver anodizing is more than a trace. Why do
> > people buy this crap? Polished aluminum is a beautiful finish in
> > itself.
>
> So what is that shiny coating on MA-2s if not clear anodizing? Or on any
> shiny bike part? It's certainly not polished aluminum.
I have a Campagnolo Mirox MTB rim which is actually polished aluminum.
That is how Campagnolo described the finish, and that's how it looks to
me. I have an aluminum ice cream scoop I hand-polished with Simichrome
that looks exactly the same. The Mirox is brighter and shinier than my
MA-2s, but I would still call the MA-2 shiny; Mavic describes the finish
as "flash brilliant." If a rim looks bright and shiny, I figure any
anodization that's there probably isn't thick enough to cause problems.
The Mirox isn't welded and machined, either, and it has sockets and
eyelets ("double eyelets"), unusual in an MTB rim. It also has weird
flared sidewalls which don't strike me as a particularly good idea. The
Mirox was discontinued two or three years ago, I think.
--
to email transpose "e" and "a"
Matt O'Toole
Jobst Brandt wrote in message <72q5ao$bcu$1...@hplms2.hpl.hp.com>...
>Keith Bontrager writes:
>
>> They don't sell well. Customers prefer anodized rims.
>
>Customers don't know what they want, they make up their minds on the
>pitch they get from the sales clerk and their friends, who have also
>been nursed on the same sales pitch.
Exactly. So, it isn't consumer demand that's driving this, it's bike
companies, who create demand by suggestion and hype. Customers might start
to prefer nonanodized rims, if they knwo of the benefits. I'll wager the
main reason they prefer anodized rims is because Mavic has been hyping them
for so many years.
>How long have we read hard
>anodized is stronger. Harder must be stronger in most peoples
>estimation. The problem is that a gullible public is driving the
>industry instead of racing teams whose buyers used to decide what got
>used.
Again, the gullible public isn't in the driver's seat. Since they don't
know what they want, they can be told and sold anything. Why not give them
the truth, instead of continuing to feed them a load 'o' baloney?
Matt O.
G.T.
>>They don't sell well. Customers prefer anodized rims.
>
>if you'd have selected the MA2 then perhaps history would have turned
>out different. Get an apprentice on the job, you'd sell plenty to
>readers of this n.g.
i just pulled my old mtn bike ma2s (with american classic front hub and
deore xt 7-speed rear) out of the closet and put them on my second bike.
the only problem is i didn't build the rear very well 9 years ago and the
rear is really out of round now. to me there are two negatives with these
rims for mtn biking, they're not deep in the center so it is difficult to
change tires (almost any other rim nowadays i can change tires without tire
levers) and they are very narrow for mtn bike tires (this does make an
excellent round profile for most tires though). however they are going to
be great for this bike because i'm going to be using narrower road and mtn
bikes tires for commuting and cyclocross and i won't be racing them much so
i won't need to do quick tire changes.
i wish i could replace the rear or at least try and get it more round.
later, greg
Tim McNamara
Brandt) wrote:
>A bicycle wheel gets about eight million stress cycles per
>thousand miles.
That's a sobering thought. My wheels had over 40,000,000 stress cycles
this year. Sort of makes good wheelbuilding practices seem more important
when put in that light.
--
What do you want me to do, to do for you while you're sleeping?
Then please don't be surprised when you find me dreaming too.
-Robert Hunter
S. Evans
Thanks for posting.
Steve Evans
Mark McMaster
> How many million stress cycles do you expect to get on these
> carabiners? A bicycle wheel gets about eight million stress cycles per
> thousand miles.
I think you misplaced the decimal point. It's more like 800,000 stress
cycles (revolutions) per 1000 miles. It's still a lot, though.
Mark McMaster
MMc...@ix.netcom.com
E Harp
john...@magna.com.au (John Stevenson) wrote:
> Mavic also used to make two wider versions of the MA2, or rather of its
> predecessor, the slightly more rounded Module E2. The E3 and E4 (back then
> I think Mavic spent more on engineering and less on marketing) were
> resp[ectively a bit wider than an E2 and quite a bit wider. The E4 in
> particular had a reputation among British cycle tourists as *the* rim if
> you wanted wheels that would resist anything short of direct nuclear
> attack.
>
> I have no idea if Mavic still makes these rims but there must be something
> similar on the market somewhere.
>
> Also, isn't there a threat on Bontrager's web site for his rims to become
> available in 700C? Did this ever happen? KB?
I am pretty sure I noticed 700c Bontrager rims spec'd on some 99 Trek bike
or other. Come to think of it, there seems to be quite a few Bontrager
products that are not currently listed on their web site that are showing
up on the parent company's various lines, including Fisher, etc.
Speaking of Bontrager, the 99 Trek 8000 I bought several weeks ago came
with Maverick rims. These rims have some sort of red coloring on the
inside and along the inside face of the rim. Are they anodized? The brake
surface is not apparently anodized - rubbing a finger along the metal
produces what must be aluminum oxide. I am not currently riding on them,
but they do look pretty hanging in the garage. : )
Ed Harp
San Jose, CA
John Stevenson
"Matt O'Toole" <ma...@deltanet.com> wrote:
>E Harp wrote in message ...
>
>>Well, all I can say is that I will forgo anodized rims next trip. Does
>>anyone make a heavier 700 mm rim (say, for touring) that is not anodized?
>>The MA 40?
>
>There's the venerable MA2, which is still avilable, although not anywhere
>near where I live. I have seen it lately in the Nashbar catalog, and maybe
>the Performance catalog, too.
>
Mavic also used to make two wider versions of the MA2, or rather of its
predecessor, the slightly more rounded Module E2. The E3 and E4 (back then
I think Mavic spent more on engineering and less on marketing) were
resp[ectively a bit wider than an E2 and quite a bit wider. The E4 in
particular had a reputation among British cycle tourists as *the* rim if
you wanted wheels that would resist anything short of direct nuclear
attack.
I have no idea if Mavic still makes these rims but there must be something
similar on the market somewhere.
Also, isn't there a threat on Bontrager's web site for his rims to become
available in 700C? Did this ever happen? KB?
--
john...@magna.com.au
Writer, editor, escaped wage slave
Owner of the MTB-OZ mailing list, Australia's on-line MTB community
ma...@abtcorp.com
explain to someone that they are more prone to cracks, and once that's
explained, many customers (especially those who are in for rebuilds of cracked
rims) will opt for rims with a different finish. The shop i managed was
successful in selling rims w/o the hard anodized finish.
the whole issue is symptomatic of how marketing influences people's buying
habits, especially in the short term. i think keith once said something to the
effect that the marketplace generally makes valid decisions in the long term,
but often makes detours in the short-term (like bio-pace, drilling parts for
lightweight, ti spokes, etc).
Until the marketplace deals with hard anodized rims you can protect yourself
by being a luddite and only buying really ancient designs (sound like any
frequent posters to this newsgroup?) -mark weaver
In article <72q5ao$bcu$1...@hplms2.hpl.hp.com>,
jbr...@hpl.hp.com (Jobst Brandt) wrote:
> Keith Bontrager writes:
>
> > They don't sell well. Customers prefer anodized rims.
>
> Customers don't know what they want, they make up their minds on the
> pitch they get from the sales clerk and their friends, who have also
> been nursed on the same sales pitch. How long have we read hard
> anodized is stronger. Harder must be stronger in most peoples
> estimation. The problem is that a gullible public is driving the
> industry instead of racing teams whose buyers used to decide what got
> used. That was before fitness became a popular pursuit, or at least
> the perception of fitness.
>
> Jobst Brandt <jbr...@hpl.hp.com>
>
-----------== Posted via Deja News, The Discussion Network ==----------
cr...@my-dejanews.com
jbr...@hpl.hp.com (Jobst Brandt) wrote:
> In this application, hard anodizing is a wear surface and prevents
> metal from being worn off as a rope slides through the loop. I think
> the climbing equipment has it right.
But it doesn't prevent wear. Ropes get grit in them and quickly
remove any anodizing. My carabiners have worn and polished
surfaces where ropes run against them. One's palms get dirty
with aluminum oxide from handling a rope in belaying.
I've retired belay carabiners from service because rope wear had
removed a substantial amount of metal.
Tom Ace
cr...@my-dejanews.com
rich...@cruzio.com
jbr...@hpl.hp.com (Jobst Brandt) wrote:
> Keith Bontrager writes:
>
> > They don't sell well. Customers prefer anodized rims.
>
> Customers don't know what they want, they make up their minds on the
> pitch they get from the sales clerk and their friends, who have also
> been nursed on the same sales pitch. How long have we read hard
> estimation. The problem is that a gullible public is driving the
> industry instead of racing teams whose buyers used to decide what got
> used. That was before fitness became a popular pursuit, or at least
> the perception of fitness.
>
> Jobst Brandt <jbr...@hpl.hp.com>
>
I agree. But it is a bigger thing than I can change. What sport,
recreation or pastime doesn't change in this way when it becomes
popular?
Racing teams are not pure in this respect either, since they change
equipment often and need sponsorship money. A mediocre part that
lasts long enough to finish a few races and perform well enough to
not be a tremendous handicap, but with big sponsorship $$ to chip
in will be pretty persuasive. I don't know if it has always been
that way, and my guess is that it hasn't.
But, whether it is good for long term durability of the parts or not
really has little to do with it, right. It is commerce, and this is a
difficult thing to change the course of.
Keith Bontrager
rich...@cruzio.com
tim...@minn.net (Tim McNamara) wrote:
> In article <72j4bp$ivh$1...@nnrp1.dejanews.com>, u...@ubcbike.com wrote:
>
> >I have first hand knowledge about all Mavic rims...they all have problems
> >around the eyelets. The nice thing about it is they do not hassle you about
> >it usually they warranty it with no problem. They make some really cool rims
> >but the fact that they crack so easily we are no longer carrying them in our
> >store.
>
> What's "really cool" about rims that are basically guaranteed to break? I
> just lost a pair of Mavic 220's- which I bought as a wheelset via mail
> order from Colorado Cyclist thinking that "silver" finished meant polished
> aluminum rather than silver anodized (buying the built wheels was
> significantly cheaper than buying the constituent parts). The front rim
> is bulging or molehilling at every ferrule and the rear has outright
> failed with cracks at at least 10 ferrules, including one large failure
> about 1 cm long.
>
> As I've said before- never again will I buy anodized rims. This is the
> second set to fail on me (the first was a pair of dark anodized Sun road
> rims).
>
> It's peculiar- rim weights have skyrocketed in the past decade, now
> weighing as much as double as rims of 20 years ago... yet the rims fail
> faster than ever. I have a pair of Rigida 13-20 clinchers which I built
> up in 1978- they're still fine. OTOH, my Mavic 220's were about a year
> old and had seen about 2,000 road miles and 25 off-road miles. My Sun
> road rims were about 2 years old and probably had about the same mileage
> on them. I thought technology was supposed to *advance.*
>
> --
> The heart has its seasons, its evenings
> and songs of its own.
> -Robert Hunter
>
This is a good example of what I was refering to in another post.
Rims do not fail around the spoke holes only because of the finish.
The M220 rims you have are light rims. They are made to look like the
M217s from the outside, but are made with less expensive processes, and
possibly with less expensive material (not sure about that, but it
happens that way sometimes) They have a relatively large
cross section and very thin walls. The stresses around the spoke
holes are high, as the bulging in the front rim due to spoke loads
demonstrates. The stresses in the rear drive side spoke holes are
even higher. The rims fail there because of that. It would fail
there if it was polished or shot peened.
There are also other things that can influence this:
Some aluminum alloys that are more prone to this kind of failure.
The extrusion process and aluminums chosen for rims is
not simple. Some are easier to extrude but weaker. Some are
sensitive to heat treatment process variables. Some pick up
substantial anisotropic properties when extruded. All of these
can affect the fatigue strength of the rim.
Solving fatigue failures around the eyelets is not as sinple as
making a decision to polish the rims.
With respect to newer and older rim designs:
There is one significant difference in the way off road rims have
evolved into lightweight, rigid components. It is common to
design a very light rim, using thin walls and a large cross section,
a rim that will perform very well for some time and be very light,
while compromising the long term durability around the spoke holes.
It works out in some ways. MTB rims commonly wear through the brake
walls rapidly, get dented on rocks, or get tacoed in crashes. Long
term durability os not the highest priority in all cases.
If one decides not to take this design route, there is no way to
drop the weight of the rim below a given level and maintain good
bending strength. Most older rims were limited by the knowledge
and cappability of the commercial extrusion industry, and the rim
designs had smaller cross sections and thicker walls. The thicker
lower wall of the rim's spoke bed was more durable when it came to
spoke loads, but this kind of cross section is not very strong in
other ways unless it is heavy.
The compromises in the fatigue strength in this type of rim section
noted by Jobst (MA2 v MA40), due to hard anodizing, are true. The
fatigue strength of the thick walls was compromised by the hard
anodizing. It shows up in road rims more often than MTB rims for
anumber of reasons.
There is nothing wrong with the newer type of design in a strict sense,
if off road racing performance is what is desired. It is a normal
exchange of characteristics between something designed for competition
and something designed for use by the public. The public is
probably not entirely aware of all this of course, and many who
are think it's fine - a cost that is not too large for the advantages
they perceive they get from it.
If very long term recreational performance is the highest priority,
then a heavier rim is appropriate. That is simple.
What is not simple is how to distribute that wisdom.
Some useful advice - do not assume that every bike part is designed like
a consumer appliance, to be used by anyone for anything without a problem,
even if it is used incorrectly of for the wrong purpose. (I know that's
an exaggeration, but you get the idea). They are not.
Very light stuff is designed (in the best of cases) for competition use.
That's good for short term performance (again, in the best of cases)and
may be good for long term durability in some cases, but that is not
necessarily the case. Handlebars can be designed light and strong, short
and long term. It's much harder to do with rims. Then think of what
F1 race car mechanics have to go through to keep one of those fine units
out on the race course. That's an extreme case, but not very different
than what you may need to do to ride a high perf, lightweight bike
every day for years and years. You will have to replace parts.
For a small increase in weight, you can ride one that lasts much longer.
And, if fashion stops driving engineering decisions, and we polish or
shot peen rims, (and do many other things differently) you can have a
slightly lighter rim with better fatigue properties. It is not difficult
to do from a technical POV.
However, Jobst is right. If this is what you want, you are in trouble.
You are a very small minority of the people buying bikes.
rich...@cruzio.com
john...@magna.com.au (John Stevenson) wrote:
> In article <72obia$j45$1...@corolla.OntheNet.com.au>,
> Simon Ward <s...@trendsetting.com.au> wrote:
>
> [posted and mailed]
>
> >So what is recommended so as I don't find myself stuck in a remote
> >Bolvian town trying to organise a replacement from a bike shop in La Paz?
>
> On the basis of what has been discussed so far, you need some heavy,
> non-anodised rims. I believe the following are available in that
> configuration, though you will probably end up having to force a bike shop
> to special order them for you:
>
> Sun Rhyno Lite
> Bontrager Mustang
>
> The Sun importer for Australia is Bike Corp in Melbourne (1800 810155);
> Bontrager is handled by Trek Bicycles Australia in Sydney (02 9299 7444).
>
> Also, I believe Velocity (07 3289 9262) do non-anodised rims. Since they
> are an Australian company it should be very easy to order such rims even if
> they are not a stock item. Their Aero Heat Deep V is intended for downhill
> mountain bike racing, weighs a shade under 600g and is tough as old boots,
> mostly by dint of the sheer quantity of metal there.
>
> cheers
>
> john
>
> --
> john...@magna.com.au
> Writer, editor, escaped wage slave
> Owner of the MTB-OZ mailing list, Australia's on-line MTB community
>
Simon,
The Maverick rim I designed is very strong. They are substantially
stronger than a Valiant, Mustang, or M517 rim. A few grams can make
a big difference in a given rim's strength.
The rim comes in two styles. One symmetrical rim for use on the front
of the bike, and an asymmetrical design for the rear. The asymmetrical
shape adds lateral strength to the rim and allows a more uniform spoke
tension in the rear wheel. I have a little blurb on th webpage about it.
The front rim weighs a little under 450g, and the rear is in the 475
range. Those weights are adjuscted for die wear. You might get some a
little lighter or a little heavier, depending on your luck or how hard
you look.
I believe these are very durable in every respect you are looking for
for long distance touring. If the Austrailian Trek importer can't get
you some, a good mail order distributor like Bike World (who is well
connected to Trek) should be able to.
They were originally made without eyelets (most wheels were built
with brass nipples when this type of rim is used). If you want to
use eyelets, later production for aftermarket sales had them. I also
have some "half eyelets", that can be inserted when a wheel is built.
They function in ever respect like an eyelet.
I believe that some are available in a bare (brushed) finish and
some are anodized with a decorative finish. I do not believe the
decorative finish degrades the fatigue performance of the rims.
We have tested that and cannot deterimne a difference in the
performance between the anodized rims and bare rims.
There is a slightly heavier rim that is very similar that has just
been put into production called the Corvair too. Same basic idea.
The design evolved out of some ideas about welding, what shape is
optimal for that process. Otherwise it is very similar.
If you really really want a stout rim, we make a rim called the
Clydsdale. It is used on tandems, and weighs a little over 500g.
It is not made in an asym version, in part because it is so strong it
doesn't need to be. As far as I know, they are only available in
a brushed finish. Again, if the Trek distributor can't or won't
get some for you, you can get some from the US mailorder firms.
I hope you can get them locally of course.
Other manufacturers probably make rims of this type as well. I don't
study their offerings in this category much, but this is the kind of
rim you need for laden, long distance touring. Stay clear of racing
rims.
If ther are any questions I can answer, please don't hesitate to
ask. Good luck with your travels.
Keith Bontrager
PS
If you really want to pay a price in weight, you can rin some DH rims
and tires. I don't think it's necessary, but 1000g of aluminum can
be pretty tough...
ceck...@aol.com
> > Also, isn't there a threat on Bontrager's web site for his rims to become
> > available in 700C? Did this ever happen? KB?
>
> or other. Come to think of it, there seems to be quite a few Bontrager
> products that are not currently listed on their web site that are showing
> up on the parent company's various lines, including Fisher, etc.
You're right, I just checked the Trek web site and they spec Bontrager
Fairlane rims (ASYM rear) on their touring bikes. I'm definitely
interested, I'd like to know more about these. Let's hope a web site
update is in the works.
rich...@cruzio.com
All right, all right.
A Fairlane is a Corvair rolled to 700c.
A Corvair is a Maverick rim section adapted to the welding process.
It got a few grams heavier in the process. It, like the Fairlane
is primarily an OE rim. I do not know if it will be available by
itself. They are heavy (about 460g - 500g) and durable, the sort of
thing you want to put on machine built wheels going to the general
public on mid priced MTBs. They are great for that.
The Corvair and Fairlame are available in a powder coated finish
in addition to the brussd finish. Dunno if they ever get anodized.
Probably doen't matter much on a rim of this shape with respect
to spoke bed fatigue. They are strong.
These rims have a place in a lot of applications, but the way rims
and wheels are sold, there is very little demand for them. Customers
for inexpensive wheels do not build their own, and do not pay shops
to build them. They buy prebuilt wheels, typically about the same
quality as those that come on bikes (actually the same wheels offered
by bike companies as replacements), because they are servicable
(not great, not that bad if you don't beat on them) and because they
are very cheap. So few customers want heavier rims that they are typically
not thought of as a viable aftermarket product. Independent of the
logic that is put forth in this thread, which I happen to believe is
right (for the most part) these are the facts.
The rest of the old car family (to fill in the blanks):
A Maverick is the basic shape of the Mustang rim with a few modifications
to the corner radii to work without internal walls. It's also got
thicker brake walls, and it got heavier. A great mud rim - pretty
cheap and a little extra brake wall to give up in the abrasive stuff.
A Mustang is an improvement on the Red Label rim we made with Weinmann.
Slightly different shape, but mostly a much better manufacturing process.
It's light (400g F, 425g R), too light for laden touring and long term
use in the mud.
A Valiant is an improvement to the Mustang design, removing the inner
walls from the front rim. Front rims don't need them, but I left them
in the Mustang front rim because there was no ASYM design when I did
it originally, and experience showed that many people used the front
rims I designed on the back of their bikes to save a few grams, so
it had to be able to work there. That requirement ended with the
ASYMs. The Valiant front rim is light and a front rim only at 360g
(though several shop guys stuck them on the back of their bikes immediately
just to mess with my head) and it has an ASYM cousin at 400g. These
are not for extended use in the mud unless they have coated sidewalls
to eliminate brake wall wear. These are the F1 car analogy rims. Great
when they are in good shape, but probably not an extremely long life
in service in hard all season use with uncoated brake walls. No
surprise really. Right?
A Clysdale and a Mack are the same very heavy duty rim, rolled to
different sizes, and a Bruiser is a BMX mongrel, heavier than you
want to know about. But strong.
The staff in the midwest assure me that they have everything under control
with the website. We used to run it from here, but changes in staff
here meant that they got to do it. Bet you're on the edges of your seats...
KB
Jobst Brandt
>> How many million stress cycles do you expect to get on these
>> carabiners? A bicycle wheel gets about eight million stress cycles
>> per thousand miles.
> I think you misplaced the decimal point. It's more like 800,000 stress
> cycles (revolutions) per 1000 miles.
Thanks. I've gotta watch those zeros more closely.
Jobst Brandt <jbr...@hpl.hp.com>
G.T.
>
>The staff in the midwest assure me that they have everything under control
>with the website. We used to run it from here, but changes in staff
>here meant that they got to do it. Bet you're on the edges of your
seats...
>
>KB
Yep!
Matt O'Toole
cr...@my-dejanews.com wrote in message <72qi3c$h9o$1...@nnrp1.dejanews.com>...
>In article <72q1ja$bcu$8...@hplms2.hpl.hp.com>,
> jbr...@hpl.hp.com (Jobst Brandt) wrote:
>
>> In this application, hard anodizing is a wear surface and prevents
>> metal from being worn off as a rope slides through the loop. I think
>> the climbing equipment has it right.
>
>But it doesn't prevent wear. Ropes get grit in them and quickly
>remove any anodizing. My carabiners have worn and polished
>surfaces where ropes run against them. One's palms get dirty
>with aluminum oxide from handling a rope in belaying.
>I've retired belay carabiners from service because rope wear had
>removed a substantial amount of metal.
That's what the steel ones are for. A couple of extra ounces there ain't
gonna kill ya. Tell that to the average climber, though, who absolutely
must have the latest/lightest stuff. Sound familiar?
Matt O.
David Garza
online catalogs, and it's not explicit whether rims that are "silver" are in
fact unanodized or just anodized in silver.
Thanks -- David
Jobst Brandt wrote:
>
> Matt O'Toole writes:
>
> > There's the venerable MA2, which is still avilable, although not
> > anywhere near where I live. I have seen it lately in the Nashbar
> > catalog, and maybe the Performance catalog, too.
>
Matt O'Toole
cr...@my-dejanews.com wrote in message <72t3i0$opq$1...@nnrp1.dejanews.com>...
>In article <72sg07$m...@journal.concentric.net>,
>> >removed a substantial amount of metal.
>>
>> That's what the steel ones are for. A couple of extra ounces there ain't
>> gonna kill ya. Tell that to the average climber, though, who absolutely
>> must have the latest/lightest stuff. Sound familiar?
>
>carabiner material,
>A lead climber may commonly carry 25 or more carabiners; using steel ones
>instead of aluminum would be extra pounds, not ounces. And weight makes
>much more difference in climbing than in bicycling, as evidenced by the
>slim physiques of the best climbers.
One steel carabiner adds just a couple of ounces.
>and most climbers are not so fanatical about gear.
Baloney. Boys and their toys, just like mountain bikers. BTW, if you want
a big belay 'biner, and steel is too heavy for you, they also make titanium
ones.
>In any case, the only carabiner I wear through is the one used
>at the belay device, and I get about five years of service out
>of one. That's not a compelling reason for me to switch to steel.
That's fine, but it all depends on how many people and bags you're belaying
and hauling, how far, and how often.
Matt O.
E Harp
> A Mustang is an improvement on the Red Label rim we made with Weinmann.
> Slightly different shape, but mostly a much better manufacturing process.
> It's light (400g F, 425g R), too light for laden touring and long term
> use in the mud.
Is this a question of gross weight or carrying weight other than on the
seat and pedals?
Rider weight varies by as much as several hundred pounds. I only ask
because I am by the former definition always doing "laden touring."
Ed Harp
San Jose
John Stevenson
rich...@cruzio.com wrote:
>The Maverick rim I designed is very strong.
Whoops. That's the rim I was thinking of. Serves me right for trying to
quote rim names from memory, especially when they both start with 'm'.
cr...@my-dejanews.com
> >I've retired belay carabiners from service because rope wear had
> >removed a substantial amount of metal.
>
> That's what the steel ones are for. A couple of extra ounces there ain't
> gonna kill ya. Tell that to the average climber, though, who absolutely
> must have the latest/lightest stuff. Sound familiar?
You paint an inaccurate picture. Aluminum is a perfectly reasonable
carabiner material, and most climbers are not so fanatical about gear.
A lead climber may commonly carry 25 or more carabiners; using steel ones
instead of aluminum would be extra pounds, not ounces. And weight makes
much more difference in climbing than in bicycling, as evidenced by the
slim physiques of the best climbers.
In any case, the only carabiner I wear through is the one used
at the belay device, and I get about five years of service out
of one. That's not a compelling reason for me to switch to steel.
Tom Ace
cr...@my-dejanews.com
andrew s mein
Drew
rich...@cruzio.com wrote in message <72qkq3$jn6$1...@nnrp1.dejanews.com>...
(lots o' rim stuff)