MA3 rim failure
maxo
got pulled out--but a whole section of rim pulled away from the
sidewalls. Ironic since I've always been one to defend these Mavics
with my anecdotal experience.
So the rumors are true--they're crap rims. :/ Mavic really should do a
recall on these--it's rediculously bad engineering.
FWIW, It's a 36H dark anodized version that I picked up from Nashbar. I
got it prebuilt on a Sora hub. Decent enough budget wheel after a
retruing. I didn't tighten the spokes more than a 1/4 turn from what
the original builder did--and I've trued a lot of wheels--these felt
nowhere near overtight.
I'm 175ish pounds and ride on pavement with 28mm tires, so nothing out
of the ordinary there. About 10K miles on the rim.
Any suggestions for a budget rear wheel I can get for cheap on line?
I'm through with Mavic, even though I'm sure some OpenPros would be
fine. Weight is not an issue, as it's going on my bomb proof urban
single speed. Perhaps time to learn how to build a wheel...
maxo
[img]http://static.flickr.com/28/63006286_9beffee93e_o.jpg[/img]
Llatikcuf
maxo wrote:
>
> FWIW, It's a 36H dark anodized version that I picked up from Nashbar. I
> got it prebuilt on a Sora hub. Decent enough budget wheel after a
> retruing. I didn't tighten the spokes more than a 1/4 turn from what
> the original builder did--and I've trued a lot of wheels--these felt
> nowhere near overtight.
>
The infamous dark anodized rims..... You might want to search the
archives concerning these.
-Nate
Callistus Valerius
> got pulled out--but a whole section of rim pulled away from the
> sidewalls. Ironic since I've always been one to defend these Mavics
> with my anecdotal experience.
>
> So the rumors are true--they're crap rims. :/ Mavic really should do a
> recall on these--it's rediculously bad engineering.
>
Kind of disappointing, I had a rear MA3 with 3 cracks in the rim, coming
from the holes, and I retired the wheel. Front one works ok, so I got an
open pro on the back. They look like the same wheelset, so it doesn't look
like a mismathed wheelset.
Andy Morris
I've had a similar failure on MA3's. I got some Ambrosio Excellence rims to
replace them.
Its purely subjective but they felt a lot more solid when building and the
creaking noises I thought were coming from the BB stopped with the new rims.
--
Andy Morris
AndyAtJinkasDotFreeserve.Co.UK
Love this:
Put an end to Outlook Express's messy quotes
http://home.in.tum.de/~jain/software/oe-quotefix/
jobst....@stanfordalumni.org
> Felt a rub on the fender stay and was shocked to see--not a eyelet
> that got pulled out--but a whole section of rim pulled away from the
> sidewalls. Ironic since I've always been one to defend these Mavics
> with my anecdotal experience.
> So the rumors are true--they're crap rims. :/ Mavic really should do
> a recall on these--it's ridiculously bad engineering.
> FWIW, It's a 36H dark anodized version that I picked up from
> Nashbar. I got it prebuilt on a Sora hub. Decent enough budget wheel
> after a re-truing. I didn't tighten the spokes more than a 1/4 turn
> from what the original builder did--and I've trued a lot of
> wheels--these felt nowhere near over tight.
> I'm 175ish pounds and ride on pavement with 28mm tires, so nothing
> out of the ordinary there. About 10K miles on the rim.
> Any suggestions for a budget rear wheel I can get for cheap on line?
> I'm through with Mavic, even though I'm sure some OpenPros would be
> fine. Weight is not an issue, as it's going on my bomb proof urban
> single speed. Perhaps time to learn how to build a wheel...
Where's jim beam (aka Southern Comfort) when we need him. He can
explain why this is all your fault and not the anodizing that causes
fractures of this kind. As I have often explained, in the days of
yore there were no rim fractures and that suddenly became prevalent
with the first hard anodized Mavic rims that were advertised to be
much stronger as a result of their surface finish.
Cosmetic (clear and colored) anodizing is relatively benign, being too
thin to cause stress cracks from propagating from the crust into the
base metal. Polished aluminum with no anodizing is better yet. I
rode on those for many years without cracks, as did my riding
companions. My two sets of wheels are still standing there, oxidized
to a dull grey after all these years, for lack of anyone who wants to
ride tubular tires.
Jobst Brandt
jim beam
so when did you ever attend materials lectures jobst? did you ever
discover where the library was? weren't you ever told that a dye
penetrant tests merely confirm existance of cracks, not the cause?
because that's only "evidence" you've ever presented for your "anodizing
causes cracking" theory. and a jolly old laugh it is too. particularly
when we have clear evidence that the crack lines follow the extrusion,
NOT cracks in the anodizing. we even have photographic evidence of your
famous siver ma2's confirming this cracking behavior, not that you ever
care to address that episode because it leads into your other favorite
subject, excess spoke tension. and let's conveniently forget that the
sudden onset of cracking just happened to coincide with publication of
your book shall we? "tension as high as the rim can bear" indeed.
>
> Cosmetic (clear and colored) anodizing is relatively benign, being too
> thin to cause stress cracks from propagating from the crust into the
> base metal. Polished aluminum with no anodizing is better yet.
sure. in palo alto. for anyone else where corrosion and corrosion
induced cracking are concerns, anodizing will significantly prolong the
service life of the rim. that's /why/ it's done. you should check into
the corrosion characteristics of rim alloy classes like 6061 & 6106. i
know that's wishful thinking on my part that you should ever condescend
to check a fact before forming an opinion, but it might mitigate your
credibility problem.
> I
> rode on those for many years without cracks, as did my riding
> companions. My two sets of wheels are still standing there, oxidized
> to a dull grey after all these years,
are these your famous 300k mile wheels? the ones with no dish? and the
ones with the replaced rims, replaced hubs and replaced spokes? but
they're still the same old wheels?
jim beam
check back in the archive. peter chisholm has a word or two to say
about ma3's.
you'll also find the manufacturer spoke tension spec. ~800N iirc. if
your tension is over that, you're definitely going to increase cracking
propensity.
daveornee
bike) must not exceed the following values:
- Road rims: 100 kg (except for MA3: 85 kg)"
Quoted from tech-mavic.com;
You were right at the weight limit for MA3 rim. Rear usually has
signifcantly more load on the right spokes due to the spoke support
angles involved.
If you got 10k out of them I would say you did pretty good for those
cheap rims.
Mavic OpenPro is rated for 100 kg so you would do better with them.
Ambrosio and Torelli make some pretty nice rims, but I have had my best
results with Velocity rims.
--
daveornee
Michael Press
<1131926048....@g47g2000cwa.googlegroups.com>,
"maxo" <land...@gmail.com> wrote:
You still have the hubs? Get Sun CR-18 rims and build them up.
--
Michael Press
maxo
daveornee wrote:
> "The total weight of the rider and his/her equipment (not including the
> bike) must not exceed the following values:
> - Road rims: 100 kg (except for MA3: 85 kg)"
> Quoted from tech-mavic.com;
> You were right at the weight limit for MA3 rim. Rear usually has
> signifcantly more load on the right spokes due to the spoke support
> angles involved.
> If you got 10k out of them I would say you did pretty good for those
> cheap rims.
> Mavic OpenPro is rated for 100 kg so you would do better with them.
> Ambrosio and Torelli make some pretty nice rims, but I have had my best
> results with Velocity rims.
That's absolutely absurd! I'm not going to check or doubt your
quotation legitimacy--but 175# of quite lean 6'2" rider and a fairly
light 23# bike is pushing the limit of a rim? A 36H rim that some
folks tour on?! Yowsah! I'm about 82kg with my gear on--I don't think
my weight was the issue, more like these rims are brittle crap. I've
ridden lots of different rims--all moderate to budget, with big loads
to boot, and never had any issues short of having to true a wheel every
year or two.
To be honest, I don't have a computer on the bike, so the mileage might
be closer to 7K--but I expect a 36H sturdy road rim to last 50K short
of some sort of accident involving egregious impact.
Though I'm tempted to eschew Mavic rims forever, those cxp22s are
rather budget and sturdy looking on paper, but I wonder about real life
strength. Will have to call the LBS tomorrow and see what they have,
I'm tempted to do a Jobst Brandt Switcheroo Sandwich to avoid having to
build the wheel from scratch.
Bruce Graham
land...@gmail.com says...
might be near the end of their life anyway. Have you checked? It is
hard to tell from the photo, but there is some wear.
BeeCharmer
in crits. Check out the Velocity rims. I built up a pair of Pro Elits
(Deep V tubular) and they've been great for the past 1000 miles.
www.worldclasscycles.com
chris
Qui si parla Campagnolo
maxo wrote:
> Felt a rub on the fender stay and was shocked to see--not a eyelet that
> got pulled out--but a whole section of rim pulled away from the
> sidewalls. Ironic since I've always been one to defend these Mavics
> with my anecdotal experience.
>
> So the rumors are true--they're crap rims. :/ Mavic really should do a
> recall on these--it's rediculously bad engineering.
Yep, it only took us about a dozen failures before we stopped selling
them. mavic...what a hoot.."really, we haven't heard of that"....
>
> FWIW, It's a 36H dark anodized version that I picked up from Nashbar. I
> got it prebuilt on a Sora hub. Decent enough budget wheel after a
> retruing. I didn't tighten the spokes more than a 1/4 turn from what
> the original builder did--and I've trued a lot of wheels--these felt
> nowhere near overtight.
>
> I'm 175ish pounds and ride on pavement with 28mm tires, so nothing out
> of the ordinary there. About 10K miles on the rim.
>
> Any suggestions for a budget rear wheel I can get for cheap on line?
> I'm through with Mavic, even though I'm sure some OpenPros would be
> fine. Weight is not an issue, as it's going on my bomb proof urban
> single speed. Perhaps time to learn how to build a wheel...
Velocity Fusion or Aero. great rims and there's nothing wrong with the
hub. Find somebody to re-use the hub. I can...call me.
Qui si parla Campagnolo
You are wrong to imply it's the rider weight that causes these to fail.
Many we built were for 125 pound women and they had eyelets pull out
anyway. Many fronts also. If a rim can't support 45% of a rider's 200
pound weight, it IS crap and these certainly were.
Lister
Isn't the main issue that the MA3 has single eyelets on the inner
surface only, while the MA2 and Open pro have double eyelets that join
the inner and outer surfaces? Wouldn't that make more difference than
the anodizing?
David L. Johnson
> after 10K miles, depending on your terrain and weather, the sidewalls
> might be near the end of their life anyway. Have you checked? It is
> hard to tell from the photo, but there is some wear.
For road wheels, 10k miles is a short lifespan for the sidewalls.
--
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
(_)/ (_) |
maxo
expensive) fancy Bontrager brake shoes in the first thousand miles, but
soon switched to classic KoolStop continentals that don't seem to wear
the rim at all.
Well, I'm gonna call the LBS and see if they have a rim with the same
rough depth so I can just transfer hub and spokes a la Jobst.
Otherwise I'm just going to get another set of on sale Nashbar wheels
and destress and tune them myself--has always worked for me in the
past, cheaper than buying the the individual parts, and I don't like to
have more wheel than I can afford to have stolen.
Those cheap Mavic CXP22 rims all right? I see them specced on bikes
ranging from $800 to $2000 bucks and Mavic claims a higher weigh limit
for them. Searching the newsgroup returns no horror stories.
Jay Beattie
"Lister" <lister...@telus.net> wrote in message
news:1131981355.1...@z14g2000cwz.googlegroups.com...
Yes and no. For example, in my experience, the anodized G40s had
a higher failure rate than their non-annodized equivalent, the
MA2/E2/ModE; they were not saved by the socket design. I pulled
spokes through G40s, GP4s, Open Pros, etc. but never through a
non-anodized MA2. The socket probably helps spread the load
between the inner and out walls, but it does not prevent failure
in anodized rims. I switched to an OC design (Velocity Aerohead)
because it allowed me to build a straight wheel with reasonable
tensions that do not overly stress the spoke hole. -- Jay
Beattie.
Warren Block
>
> You still have the hubs? Get Sun CR-18 rims and build them up.
For those of us with otherwise-good wheels with MA3 rims:
Is there a decent, easy-to-get rim with the same ERD (607.5mm) as the
MA3?
--
Warren Block * Rapid City, South Dakota * USA
maxo
My eyeball tells me those Sun cr18s should be a drop in fit for an MA3
if you want to recycle hub and spokes.
http://www.starbike.com/images/SUN/hires/cr18l7.jpg I'd still make
absolutely sure.
stack the old wheel on top of the new rim and transfer them spoke by
spoke. Don't even try this w/o an electric screwdriver unless you want
carpal tunnel. Of course--don't re-use old spokes to build wheels in
any other way.
I got a cheap set of cxp22s 32H built on some scrappy Sora's for $85.
Repack and retrue--and they should last much longer than boutique
wheels. Would have grabbed a set with Sun rims, but was too lazy to
search for prebuilts. :P
Art Harris
> My eyeball tells me those Sun cr18s should be a drop in fit for an MA3 if you want to recycle hub and spokes.
Spokecalc lists the CR18 as 612 mm ERD.
Art Harrris
maxo
cross section compared to the Sun CR18 only differs by 0.5mm. However
the Sun CR17a is 607mm--close enough to swap, but a little hard to find
in 700c--I'm only seeing it in 26". However the Velocity Razor and
Vuelta Vision are also 607mm--close enough.
Chalo
> Felt a rub on the fender stay and was shocked to see--not a eyelet that
> got pulled out--but a whole section of rim pulled away from the
> sidewalls. Ironic since I've always been one to defend these Mavics
> with my anecdotal experience.
>
> So the rumors are true--they're crap rims. :/ Mavic really should do a
> recall on these--it's rediculously bad engineering.
>From what I can tell, _all_ recent Mavic rims are utter crap.
I had a problem with a T519 rim recently where the rims started to fail
in compression from the tension of 48 spokes. This wouldn't be all
that unusual, except for where the failure occurred: Not at the valve
hole, but at the weld. The weld began to bulge and ripple, which was
quite visible due to the machined finish traversing that area.
Mavic not only use 6106 aluminum, which is the weakest 6000-series
aluminum, but it appears that they don't even heat treat after welding.
That's their way of making a heavy rim with the strength of a light
one, I guess. I'm not impressed.
I developed a sense of what Mavic rims were like back in the days of
the Module 3 & 4, MA2, and Oxygen M6. There was an obvious drop in
durability and finish with the introduction of the M231/261/281 around
1990, but every update from them since then seems to have elevated
their crappiness quotient. It's difficult to see how they've managed
to raise their prices all this time-- but I suppose that pricing is
their only remaining claim on offering a premium product.
Adidas Salomon bought Mavic at some point, and now it appears that
Mavic rims are made like Adidas shoes-- that is, poorly and quickly out
of the cheapest materials available, to last a short time yet command a
high price.
Chalo Colina
kwalters
I had a silver MA3 develop radiating cracks from 5 or 6 of the eyelets;
had about 5000 miles when I first noticed them, so they were probably
there sooner. I replaced it this summer with a
bought-from-Nashbar-several-years-ago dark anodized MA3 I had hanging in
the garage. Oh well.
Ken (who still has another unused dark anodized MA3 hanging in the garage)
41
Chalo wrote:
> I developed a sense of what Mavic rims were like back in the days of
> the Module 3 & 4, MA2, and Oxygen M6. There was an obvious drop in
> durability and finish with the introdu ction of the M231/261/281 around
> 1990, but every update from them since then seems to have elevated
> their crappiness quotient. It's difficult to see how they've managed
> to raise their prices all this time-- but I suppose that pricing is
> their only remaining claim on offering a premium product.
>
> Adidas Salomon bought Mavic at some point, and now it appears that
> Mavic rims are made like Adidas shoes-- that is, poorly and quickly out
> of the cheapest materials available, to last a short time yet command a
> high price.
Whoa- the last Adidas shoes I bought (4 years ago?) were a pair of
leather Countrys, made in Vietnam. They are great quality and I love
them- I use them exclusively for bicycle riding though. Pair before
that were Galaxies, very well made, stood up to a lot (the thin black
rubber outsole eventually came loose from one though, a common fault
with that construction).
The Tigers and Pumas I've bought more recently are also excellent.
jim beam
jay, you never did get back to us on the spoke tension you use. i
recall your problems with pulling sockets through open pros from a while
back, but that's one heck of a rare occurrance and i seriously doubt
it's possible at spoke tensions anywhere near manufacturer spec.
and silver ma2's /are/ anodized, just so you know.
RonSonic
Open 4 CD still true, still uncracked, I weigh 220 and ride cross on them.
Maybe the anodize doesn't help, but there's more to it.
Gotta be.
Ron
Llatikcuf
RonSonic wrote:
>
> Open 4 CD still true, still uncracked, I weigh 220 and ride cross on them.
>
> Maybe the anodize doesn't help, but there's more to it.
>
> Gotta be.
>
It's all good, I ride MTB on X618 CD -- No problems yet.
-Nate
David L. Johnson
>
> My eyeball tells me those Sun cr18s should be a drop in fit for an MA3
> if you want to recycle hub and spokes.
> http://www.starbike.com/images/SUN/hires/cr18l7.jpg I'd still make
> absolutely sure.
My calculator (Damon Rinard's actually) says that the Suns are 612 ERD as
opposed to the Mavic's 607.5. Old spokes won't fit. OTOH, there are
worse things than buying new spokes.
--
David L. Johnson
__o | "It doesn't get any easier, you just go faster." --Greg LeMond
_`\(,_ |
(_)/ (_) |
Chalo
>
> Whoa- the last Adidas shoes I bought (4 years ago?) were a pair of
> leather Countrys, made in Vietnam. They are great quality and I love
> them- I use them exclusively for bicycle riding though. Pair before
> that were Galaxies, very well made, stood up to a lot (the thin black
> rubber outsole eventually came loose from one though, a common fault
> with that construction).
>
> The Tigers and Pumas I've bought more recently are also excellent.
It sounds like you need to refamiliarize yourself with quality shoes.
Shoes that get squirted into a mold actually have a lot in common with
welded rims made of aluminum/cream cheese alloy. One of the things
they have in common is that I've already had as many of them as I ever
care to.
Chalo Colina
Ron Ruff
maxo wrote:
>
> Though I'm tempted to eschew Mavic rims forever, those cxp22s are
> rather budget and sturdy looking on paper, but I wonder about real life
> strength.
FWIW I've been riding on cxp22s and haven't had any problems... but
only for 5K miles. I've had other rims (mtbs) crack at the eyelets
after only 2K miles. I'd go with Velocity rims though, if the price is
similar.
Jay S. Hill
> maxo wrote:
>
>>
Velocity Razor has the same effective rim diameter. You can reuse the
same spokes and hub. I did.
Jasper Janssen
>jobst....@stanfordalumni.org wrote:
>> someone writes:
Well, I can see this is going to be a looooooong subthread.
Jasper
Jasper Janssen
>It sounds like you need to refamiliarize yourself with quality shoes.
>
>Shoes that get squirted into a mold actually have a lot in common with
>welded rims made of aluminum/cream cheese alloy. One of the things
>they have in common is that I've already had as many of them as I ever
>care to.
You mean the soles, right? I've never actually had non-rubber soles, for
one thing because I like my heart functioning and continuing to do so even
when I'm doing electrics, but do leather soles not have much less springy
effect?
Anyway, my last few pairs (Panama Jack, large sizes, size 51 euro/about 15
or so US) only wore out their soles when the inside rear bits had worn out
as well, and that stuff is real leather.
Jasper
Qui si parla Campagnolo
No-I have built with may single eyelet rims w/o problem. Single eyelet
by itself does not mean a short life for the rim. Single eyelets with
thin, brittle rim walls make for a poor rim.
daveornee
maxo Wrote:
>
> > "The total weight of the rider and his/her equipment (not including
> the
> > bike) must not exceed the following values:
> > - Road rims: 100 kg (except for MA3: 85 kg)"
> > Quoted from tech-mavic.com;
> > You were right at the weight limit for MA3 rim. Rear usually has
> > signifcantly more load on the right spokes due to the spoke support
> > angles involved.
> > If you got 10k out of them I would say you did pretty good for those
> > cheap rims.
> > Mavic OpenPro is rated for 100 kg so you would do better with them.
> > Ambrosio and Torelli make some pretty nice rims, but I have had my
> best
> > results with Velocity rims.
>
>
> quotation legitimacy--but 175# of quite lean 6'2" rider and a fairly
> light 23# bike is pushing the limit of a rim? A 36H rim that some
> folks tour on?! Yowsah! I'm about 82kg with my gear on--I don't think
> my weight was the issue, more like these rims are brittle crap. I've
> ridden lots of different rims--all moderate to budget, with big loads
> to boot, and never had any issues short of having to true a wheel
> every
> year or two.
>
> To be honest, I don't have a computer on the bike, so the mileage
> might
> be closer to 7K--but I expect a 36H sturdy road rim to last 50K short
> of some sort of accident involving egregious impact.
>
> Though I'm tempted to eschew Mavic rims forever, those cxp22s are
> rather budget and sturdy looking on paper, but I wonder about real
> life
> I'm tempted to do a Jobst Brandt Switcheroo Sandwich to avoid having
> to
> build the wheel from scratch.
Force = Mass times Acceleration
Acceleration is just gravity when you are just riding along on smooth
surfaces. Bumps, jumps, and road hazards just multiply the effect of
rider mass.
It doesn't matter how tall or lean you are.
It is hard to tell from your photograph if your spokes are straight 14
g or not, but butted spokes help spread the load and their additional
elasticity means that the spokes take up more of the cyclic flexing
that happens from just riding along.
MA3 rims are the very lowest quality road rims that Mavic made. In my
cross country touring I have seen many of them cracked in very similar
fashion to what your photograph showed. Most were not hard annodized,
but most were 36 spoke wheels. Some were custom built by well
respected builders. Mavic no longer makes MA3 rims.
--
daveornee
maxo
Ron Ruff wrote:
> maxo wrote:
> >
> > Though I'm tempted to eschew Mavic rims forever, those cxp22s are
> > rather budget and sturdy looking on paper, but I wonder about real life
> > strength.
>
> FWIW I've been riding on cxp22s and haven't had any problems... but
> only for 5K miles.
I got a set of them at Nashbar for $85 built on Sora (gasp!) hubs.
Probably an over-run from some bike manufacturer. I'll repack and
retrue and they should be fine for a couple years. I keep meaning to
get around to buying a new bike, so no need for lifetime hubs. :P
I was just going to swich out the rim, but getting two new wheels +
hubs (albeit cheesy ones) for the price of two rims was a better choice
for this rat-tastic bicicleta.
I wouldn't mind some traditional box section polished aluminum rims
sometime in the future--but that type of rim seems to be dying out. :/
As far as tension ripping out the MA3--I don't have a tensionometer,
but the pluck tone was no higher than those parts of the Star Spangled
Banner that everybody lip-synchs since they can't sing that high. :D
Chalo
>
> "Chalo" <chalo....@gmail.com> wrote:
>
> >Shoes that get squirted into a mold actually have a lot in common with
> >welded rims made of aluminum/cream cheese alloy. One of the things
> >they have in common is that I've already had as many of them as I ever
> >care to.
>
> You mean the soles, right? I've never actually had non-rubber soles, for
> one thing because I like my heart functioning and continuing to do so even
> when I'm doing electrics, but do leather soles not have much less springy
> effect?
Rubber and other elastomers are fine materials to use for shoe soles.
But there is a qualitative difference between shoes that have entire
structural components molded or bonded in place, and shoes that are
stitched to their soles. There are performance benefits to molded
construction if it is done well-- but are the manufacturers who use it
doing so for those reasons, or just because it's cheaper for them?
Because if "cheap" is the primary motivation, then they will cut other
corners, too, and and sacrifice other benefits. Sort of like Mavic has
done.
Molded/glued shoes are cheap to make (though not always cheap to buy)
and disposable, but are subject to more kinds of quality problems than
traditionally made shoes-- sort of like Mavic rims.
I think Mavic made welded rims with a problematic heat-affected zone
solely for cheaper manufacturing, then compounded their problems by
exploiting the fact that their rims couldn't support decent spoke
tension anyway, Unlike most other rim manufacturers, Mavic publish
spoke tension limits. They don't emphasize them, though, because
fundamentally that is an acknowledgement that their rims are worse than
they used to be; that they have less structural integrity than ever
before.
There are potential benefits to welded rims, if their welds are
carefully finished and the rims are heat-treated after welding. But if
you do them that way, then they will not be cheaper to manufacture than
pinned rims.
If the only thing that distinguished molded/glued shoes was their
construction techniques, then I'd probably have developed no objections
to them. Unfortunately, those construction techniques are
characteristic of manufacturers who will leave no virtue uncompromised
in the pursuit of maximum profit, and that's the real problem.
There are other construction methods, whether they be tidily pinned rim
joints or stitched sole construction, that constitute evidence of a
manufacturer placing some value on things outside the bottom line.
It's not that those manufacturers don't intend to make a profit; it's
simply an outward sign that they may have some standards about what
they are willing to do to generate that profit.
Chalo Colina
Lister
> because it allowed me to build a straight wheel with reasonable
> tensions that do not overly stress the spoke hole. -- Jay
> Beattie.
Sorry. What's "OC design"?
Ron Ruff
maxo wrote:
>
> I got a set of them at Nashbar for $85 built on Sora (gasp!) hubs.
> Probably an over-run from some bike manufacturer. I'll repack and
> retrue and they should be fine for a couple years. I keep meaning to
> get around to buying a new bike, so no need for lifetime hubs. :P
>
They are *below* Sora level... and this is my "fancy" bike, too. A
good packing with marine grease has made the hubs trouble free for 5K
miles... lots of rain riding, too. I put rubber grommets on the
axles... maybe that helped. I broke two spokes recently, though.
Another recommendation: Stress relieve the spokes, lube the eyelets,
and increase the tension a bit. The rear in particular tends to be
undertensioned, and that is bad with 14g spokes on the non-drive side.
> I was just going to swich out the rim, but getting two new wheels +
> hubs (albeit cheesy ones) for the price of two rims was a better choice
> for this rat-tastic bicicleta.
I wouldn't worry about the hubs... they should turn just fine and may
well last as long as the rest of the wheels... maybe longer.
Phil, Squid-in-Training
Look at the second rim down here:
http://www.velocitywheels.com/Road_rims.htm
--
Phil, Squid-in-Training
Jay Beattie
"jim beam" <nos...@example.net> wrote in message
news:y5Sdna5iw-6iyuTe...@speakeasy.net...
The old MA2/E2/ModEs were polished and not anodized. Later
versions of the MA2 and the Gentleman were satin anodized. I
still have a satin anodized Gentelman. I am talking about the
old, polished MA2s. In any event, I cannot honestly answer your
question about spoke tension because I only just recently bought
a tensiometer. I would guess about 120kgf right side and 100kgf
left. I built to much higher tensions with 36H/120mm E2
wheels -- and to ungodly tensions with the Super Champion Mod
58s -- with absolutely no problems ever. As for the tension on
the Open Pros/Open 4CD, they were as tight as necessary to
prevent them from going slack. I was racing a lot at 200lbs,
and probably had those at 130kgf right. I could not have run
them lower and had them stay true -- not without Loctite (or
something like it), which I prefer not to use on conventional
wheels. I think a thread lock of some sort is inevitable on the
low spoke count wheels. -- Jay Beattie.
maxo
Ron Ruff wrote:
> Another recommendation: Stress relieve the spokes, lube the eyelets,
> and increase the tension a bit. The rear in particular tends to be
> undertensioned, and that is bad with 14g spokes on the non-drive side.
>
That's what I always do with Nashbar stuff. I'm no expert wheelbuilder,
but after such a tuning I can usually go 3K+ before the rims need a
touch up. I'm of course wary of tightening spokes on a Mavic rim
though. :P LOL
> I wouldn't worry about the hubs... they should turn just fine and may
> well last as long as the rest of the wheels... maybe longer.
Last set of hubs I got on a set of wheels by Nashbar were indeed 2200's
and were missing a bearing in the front and poorly adjusted.Ten whole
minutes of my life wasted (triple gasp!). Only downsides I see are poor
seals (though the new model is supposed to be better) and that they've
got zero sex appeal.
Those cheapie wheelsets they sell are indeed a bargain if you're
mechanically inclined. :D One of these days I'll get some nice hubs
from Ebay when I have the time. I always liked the Suntour Superbe
stuff.
Jasper Janssen
>Jasper Janssen wrote:
>>
>> You mean the soles, right? I've never actually had non-rubber soles, for
>> one thing because I like my heart functioning and continuing to do so even
>> when I'm doing electrics, but do leather soles not have much less springy
>> effect?
>
>Rubber and other elastomers are fine materials to use for shoe soles.
>But there is a qualitative difference between shoes that have entire
>structural components molded or bonded in place, and shoes that are
>stitched to their soles. There are performance benefits to molded
Ah, right. Yeah, all my shoes are stitched to their soles, and have been
for at least a decade -- quite possibly starting from the time they became
big enough to require not just men's sizes (that would have been before I
entered puberty), but actual extra-large sizes from the special,
high-quality store around 14 or 15 or so.
>There are potential benefits to welded rims, if their welds are
>carefully finished and the rims are heat-treated after welding. But if
>you do them that way, then they will not be cheaper to manufacture than
>pinned rims.
How are welded rims cheaper than pinned in the first place? I'd think
slapping some pins in would be much faster and less laborious than
welding. I mean, rims get extruded into tight spirals, right (or do they
extrude straight and then spiralise?) -- as long as you make sure the
diameter of the spiral is slightly smaller than that of the finished rim,
pinning ought to be a fairly simple operation, shouldn't it?
Jasper
jim beam
you have been experiencing problems, i can't understand why. i weigh
more than you, am strong enough to get some good frame whip going in a
sprint and carry varying loads when i commute. when properly "stress
relieved" [bedded in] i've had very few problems with wheels going out
of true. and i /do/ stick to manufacturer spoke tension spec. and don't
generally use loctite. a while back i switched from campy to shimano
hubs because they have slightly better flange spacing and a
correspondingly better left/right tension ratio, and while i fancy that
could make a small difference, it's not going to be a lot.
to test why wheels might go out of true, i have built wheels without
bedding in [they go out of true immediately] and have built wheels with
"moderate" bedding in [they go out of true moderately quickly]. and
i've built wheels that are fully bedded in, i.e. where you repeat the
over-tension exercise three or more times without any further deviation.
these wheels remain perfectly true afterward and these are the wheels
that are ready to ride. believe it or not, i've also tried the spoke
squeeze method and the mavic "two hands push" method and find the latter
to be more reliable - i can use close to my full body weight without
having to rely on arbitrary hand strength, gloves, etc. excess tension
will achieve the same result in terms of true stability, but at the cost
of rim reliability - as you have seen.
now, for you, if bedding in were to be the problem, loctite would not
help you because bedding in would still occur. however, once bedding in
has been properly achieved, and you're the kind of big honking brute
that regularly slackens left side spokes, then i'd say that loctite /is/
a solution for you to consider.
regarding anodizing, i'm old enough to have bought the mod-e's when they
first came out, and have a couple of ma2's knocking about in the garage.
i can't say i recall the mod-e being polished [guess i need to dig
through mother's attic some time], but both my silver ma2's are
definitely anodized. this accords with the old mavic datasheet i have
for them too. it's not a satin finish like the modern silver anodizing
but it's a kind of faux "bright".
regarding thread lock on low spoke count wheels, my mavics are indeed
nylocked, but my shimano r540's are not. they have large aluminum
nipples that have a higher coefficient of thread friction, but no other
apparent assistance, and tension that is not far off a standard high
spoke count wheel.
anyway, it's great you bought the tensiometer. i'm confident that if
built right, you /can/ have reliable true wheels without excess tension.
41
You might consider that I weigh something like 25-33% of what you
weigh... you need to familliarize yourself with... nah, forget it.
Adidas, Puma, Tiger, etc all make RUNNING shoes. A running shoe with an
upper stitched to sole construction is high quality only in the strange
sense that a plywood board is a high-quality sheet of paper. Norwegian
welts, Goodyear welts, etc, are for heavy leather hiking boots and
street shoes. With carbon rubber tread and only a little shoe goo, for
me, the uppers wear out LONG before the soles, or before the soles
separate from the upper. I haven't had a running shoe sole separate
from the upper since... I don't know, maybe never. It is always the
upper itself that splits or rips. And rest assured I've put far more
milage on my shoes than you, in all weather.
b...@mambo.ucolick.org
> Adidas, Puma, Tiger, etc all make RUNNING shoes. A running shoe with an
> upper stitched to sole construction is high quality only in the strange
> sense that a plywood board is a high-quality sheet of paper. Norwegian
> welts, Goodyear welts, etc, are for heavy leather hiking boots and
> street shoes. With carbon rubber tread and only a little shoe goo, for
> me, the uppers wear out LONG before the soles, or before the soles
> separate from the upper. I haven't had a running shoe sole separate
> from the upper since... I don't know, maybe never. It is always the
> upper itself that splits or rips. ...
jim beam says this is because you exceeded the
manufacturer's specifications on how tight you
are allowed to tie your shoelaces.
Chalo
>
> How are welded rims cheaper than pinned in the first place? I'd think
> slapping some pins in would be much faster and less laborious than
> welding.
Pinning the rim is not a complex operation, but the ends of a pinned
rim must be cut with great precision so that the rim will remain true
when the ends are compressed together. Whatever process is employed
must also leave the cut ends with exactly the same cross-sectional
shape as the rest of the rim, or else there will be braking anomalies.
A welded rim need not be cut especially neatly or square. The cut end
vanishes into the weld, and the mess left behind is cut away in a
quick, relatively insensitive process. It takes more machinery, but a
lot less human attention, to produce a welded rim .
Mavic's welds have gotten messier of late, and the sticker used to
conceal the non-machined inward-facing portion of the weld no longer
covers the irregularities. That wouldn't bother me so much if they'd
only heat treat the thing after welding.
Chalo Colina
41
ACE!!†
Chalo
>
> You might consider that I weigh something like 25-33% of what you
> weigh... you need to familliarize yourself with... nah, forget it.
>
> Adidas, Puma, Tiger, etc all make RUNNING shoes. A running shoe with an
> upper stitched to sole construction is high quality only in the strange
> sense that a plywood board is a high-quality sheet of paper. Norwegian
> welts, Goodyear welts, etc, are for heavy leather hiking boots and
> street shoes.
Point taken.
But don't you think that folks used to run before the advent of molded
plastic shoes? Did Roger Bannister have EVA insoles and patented
pneumatic bladders in his shoes when he ran the four minute mile in
1954?
The couple of serious runners I've ever known wore what I'd consider
pretty abysmal shoes-- so shoddy, in fact, that they replaced their
shoes every month or two because the things were worn out.
> With carbon rubber tread and only a little shoe goo, for
> me, the uppers wear out LONG before the soles, or before the soles
> separate from the upper. I haven't had a running shoe sole separate
> from the upper since... I don't know, maybe never. It is always the
> upper itself that splits or rips.
Right. Adidas put a flimsy upper on their shoe because the sole will
quickly wear out anyway. Mavic make a rim with a crappy spoke bed
because their heat-affected welded rim can't take a lot of spoke
tension anyway. These things are the result of analogous cost
reduction engineering. They do reduce manufacturing costs, but they
don't result in a better product from the user's standpoint. They
don't even result in a less expensive product from the user's
standpoint-- the money saved is either rolled into expensive marketing
efforts so that the manufacturer can continue to command a premium
price for a downgraded product, or it is absorbed as higher profit
margins to enrich the corporate executives and shareholders.
Chalo Colina
maxo
only a hundred bucks I could have owned one of these:
http://www.nycbikes.com/item.php?item_id=472
That's right--a three speed hub that has threading on the opposite
side--think loctite and fixie.
A three speed and fixie all in one, I couldn't have dreamed up anything
cooler! Well, the fixed SA hubs are pretty nice too.
Too bad it just comes with a grip shifter which pretty much makes drops
out of the question.
Phil, Squid-in-Training
> tried the spoke squeeze method and the mavic "two hands push" method
Can you elaborate on what this method entails?
--
Phil, Squid-in-Training
dvt
> Mavic make a rim with a crappy spoke bed
> because their heat-affected welded rim can't take a lot of spoke
> tension anyway. These things are the result of analogous cost
> reduction engineering. They do reduce manufacturing costs, but they
> don't result in a better product from the user's standpoint. They
> don't even result in a less expensive product from the user's
> standpoint-- the money saved is either rolled into expensive marketing
> efforts so that the manufacturer can continue to command a premium
> price for a downgraded product, or it is absorbed as higher profit
> margins to enrich the corporate executives and shareholders.
I gotta ask... Why don't we see someone stepping in and filling the void
with a higher quality product? Or is that already happening with a
company like Velocity, but it's just happening gradually?
--
Dave
dvt at psu dot edu
Qui si parla Campagnolo
Warren Block wrote:
> Michael Press <ja...@abc.net> wrote:
> >
> > You still have the hubs? Get Sun CR-18 rims and build them up.
>
> For those of us with otherwise-good wheels with MA3 rims:
>
> Is there a decent, easy-to-get rim with the same ERD (607.5mm) as the
> MA3?
>
> --
> Warren Block * Rapid City, South Dakota * USA
I believe that the new for 2006 mavic Open Sport is...I'll check today.
It is the replacement for the MA-3..made better according to the rep
and Mavic....we'll see,,,
jim beam
>>are the wheels that are ready to ride. believe it or not, i've also
>>tried the spoke squeeze method and the mavic "two hands push" method
>
>
> Can you elaborate on what this method entails?
it's in the previous munson thread. it's also on the mavic web site.
Chris Zacho The Wheelman
Mavic MA rims. I forget which model, but I do remember thay had a blow
out and upon brief examination it was noticed that a 2 cm piece of the
sidewall was missing!
- -
Chris Zacho ~ "Your Friendly Neighborhood Wheelman"
"May you have the winds at your back,
And a really low gear for the hills!"
Chris'Z Corner
http://www.geocities.com/czcorner
Chris Zacho The Wheelman
yet. Have there been any reports of failure with these?
I weigh 170 lbs (77kg), and use them for the street.
Chris Zacho The Wheelman
taken those "naturally anodized" rims off your hands. </sigh>
Phil, Squid-in-Training
Low-mileage riders (most) don't notice, and most people I know replace rims
due to potholes, accidents, etc. instead of mileage/brake surface erosion.
But then again I ride with college kids.
--
Phil, Squid-in-Training
dvt
> dvt wrote:
>>I gotta ask... Why don't we see someone stepping in and filling the
>>void with a higher quality product? Or is that already happening with
>>a company like Velocity, but it's just happening gradually?
> Low-mileage riders (most) don't notice...
Most low-mileage riders will take the advice of a seasoned rider or
their LBS if they're buying something with Mavics (not a department
store bike). So if there were a significantly better product, I think it
would eventually gain market share.
> ...and most people I know replace rims
> due to potholes, accidents, etc. instead of mileage/brake surface
> erosion.
You make a very good point here. It's pretty hard to tell whether a
better rim would have survived a specific event, so maybe we'd never
know if a rim were better. If we can't tell the difference, then the
poorer rim is good enough.
Jay Beattie
Go to http://www.bikeville.com/tires.html and check the clincher
rims. They have the E2s and MA2 (and Gentlemen) which all look
polished to me. -- Jay Beattie.
David L. Johnson
> I gotta ask... Why don't we see someone stepping in and filling the void
> with a higher quality product? Or is that already happening with a
> company like Velocity, but it's just happening gradually?
There is another effect on this, in that so many riders who would be in a
position to know -- those who ride several thousand miles per year, are
composed of two camps: those who buy boutique wheels and replace them
both any time something goes wrong or someone has an even fancier wheel,
and those who have been building their own wheels for years and already
avoid MA3s.
I am amazed by the increasing percentage of riders in the first camp.
They must have a lot of money to spend on things like this -- personally
I'd choke on the idea of spending $1000 on a pair of wheels. Heck, $100
is beyond what I'd consider now that I have lots of good hubs. But most
riders I see on group rides have these name-brand fancy-ass wheels. One
guy last Sunday had wheels with 3 flanges -- and even with an extra flange
they didn't have a full complement of spokes. Go figure.
--
David L. Johnson
__o | You will say Christ saith this and the apostles say this; but
_`\(,_ | what canst thou say? -- George Fox.
(_)/ (_) |
Warren Block
>
> Warren Block wrote:
>> Michael Press <ja...@abc.net> wrote:
>> >
>> > You still have the hubs? Get Sun CR-18 rims and build them up.
>>
>> For those of us with otherwise-good wheels with MA3 rims:
>>
>> Is there a decent, easy-to-get rim with the same ERD (607.5mm) as the
>> MA3?
>
> It is the replacement for the MA-3..made better according to the rep
> and Mavic....we'll see,,,
Interesting, but the probably the only way I'd be tempted to get new
rims from Mavic would be if Mavic offered a credit for the MA3s.
daveornee
the MA3. Same dimensions, but the Open Sport has an External Wear
Indicator (small groove in braking surface). My eyes may be tricking
me, but it appears that the material thickness of the top wall, where
the eyelets, are is thicker on the Open Sport than the MA3. This would
be a good idea.
Internally, the extrusion has a couple of other details that are
different in the "hidden" round sections of the MA3 now irregular ovals
in the Open Sport, and the bottom wall where the inner tube rests is now
flat instead of rounded.
--
daveornee
41
Chalo wrote:
> But don't you think that folks used to run before the advent of molded
> plastic shoes? Did Roger Bannister have EVA insoles and patented
> pneumatic bladders in his shoes when he ran the four minute mile in
> 1954?
Well, I'll admit I don't know anything about the modern weird shoes
with sproings and so on. The ones I get are very straightforward.
I don't know what Paavo Nurmi's reindeer-skin shoes were like, but
Jesse Owen's 1936 shoes, made in the factory of a certain Herr Dassler
which you seem to dislike particularly, are said to have weighed about
a pound, presumably for the pair. If true that would put them in the
same league as a very lightweight trainer or sturdy racing flat today.
Sprint spikes had gotten down to 4.5 oz in size 9 by the late 1970s
(there's been no improvement since then). For running, that's a major
difference.
Roger Bannister's are in a museum in England, I haven't seen them, and
Kolehmainen's (1912) are in the Sports Museum of Finland. I hope to one
day pass by. Very lightweight shoes can be made of thin suede leather
with a stitched sole, but the first problem is that without spikes,
leather soles are way too slippery, and if tough enough to provide
protection, they are heavy and stiff. So, rubber has been bonded to the
bottom for probably as long as rubber has been around, certainly more
than a century, and the problem then is how to make that bond stick and
how to make that rubber last. I believe the weight reduction that first
got sprint spikes down to 4.5oz (Adistar) from what must have been
about an ounce or two more in the 1960s was replacement of the rubber
outsole with some synthetic, not change of the upper from suede to
nylon.
> Adidas pu t a flimsy upper on their shoe because the sole will
> quickly wear out anyway.
In my experience, the running shoes of today are vastly more durable
than those of say, 15-35 years ago and more. Suede uppers cracked and
split with foul weather abuse, smooth leather would too if not greased
or waxed, which no one did, and gum rubber soles required constant
applications of hot glue or shoe goo to last. Thin carbon rubber
outsoles have made a huge difference (although once in a while they
unglue), as have plastic heel counters (instead of cardboard? leather?)
and polyester mesh uppers, and the glues are stronger. The only weak
spot is the lining at the heel, since nowadays it is stuffed fabric
instead of smooth vinyl or leather. Even 50 years ago and more,
training shoes had bonded rubber outsoles, not leather.
I have medium-thick leather upper running shoes (Adidas Country) and
they are great, I doubt I will every wear through the upper, but they
would be hot for the summer, and they're not as easy-care as polyester
mesh. Running shoes have to be used in ALL conditions, including salty
slush. Since they have fast-wearing gum rubber outsoles, I use them for
bicycling instead.
Nuck 'n Futz
> Well, I'll admit I don't know anything about
So you just KNOW something long-winded will follow!
Told ya so.
N&F :-P
jobst....@stanfordalumni.org
>>>> You still have the hubs? Get Sun CR-18 rims and build them up.
>>> For those of us with otherwise-good wheels with MA3 rims:
>>> Is there a decent, easy-to-get rim with the same ERD (607.5mm) as
>>> the MA3?
>> I believe that the new for 2006 Mavic Open Sport is...I'll check
>> today. It is the replacement for the MA-3..made better according
>> to the rep and Mavic... we'll see,
> Yes, take a close look at the Open Sport extrusion and compare it to
> the MA3. Same dimensions, but the Open Sport has an External Wear
> Indicator (small groove in braking surface). My eyes may be
> tricking me, but it appears that the material thickness of the top
> wall, where the eyelets, are is thicker on the Open Sport than the
> MA3. This would be a good idea.
The inner wall of the rim has been made heavier to avoid having to use
sockets for spoke support as the MA-2 did. The MA-3 just ignored that
and relied on the infinite goodness of users to not put any load on
these "beginner (aka entry level) rims". To make up for that, the rim
is anodized, welded and machined and weighs an advertised 490g.
That's what you get for only eyelets without spoke sockets.
> Internally, the extrusion has a couple of other details that are
> different in the "hidden" round sections of the MA3 now irregular
> ovals in the Open Sport, and the bottom wall where the inner tube
> rests is now flat instead of rounded.
I see no functional effect of that shape other than that a central
trench is provided for easier tire mounting. What the inner tube does
is immaterial, it being a highly flexible and adaptive bladder that
conforms to almost any shape at inflation pressures.
So how much are they asking for this jewel?
Jobst Brandt
jim beam
<snip to good bit>
>
> Go to http://www.bikeville.com/tires.html and check the clincher
> rims. They have the E2s and MA2 (and Gentlemen) which all look
> polished to me. -- Jay Beattie.
that's a good blast from the past.
fwics;
ma2 looks anodized
mod-e looks polished
super champ looks polished but dusty
gentleman looks polished
and don't forget, rim alloys have changed over time. some are more
susceptible to corrosion than others, hence the need to anodize.
dvt
> and don't forget, rim alloys have changed over time. some are more
> susceptible to corrosion than others, hence the need to anodize.
What do they use now? I thought 6061 was the standard choice for rims.
SriBikeJi
Here's what Nashbar says about these two rims:
Mavic MA3 Road Rim
A great high quality rim for all types of road riding.
Mavic MA40 CD Road Rim
These won’t last long!
Jasper Janssen
<jbea...@lindsayhart.com> wrote:
[cut out 270+lines of quoted material]
>Go to http://www.bikeville.com/tires.html and check the clincher
>rims. They have the E2s and MA2 (and Gentlemen) which all look
>polished to me. -- Jay Beattie.
Jesus man, learn to snip.
Jasper
Qui si parla Campagnolo
Chalo wrote:
>
> I had a problem with a T519 rim recently where the rims started to fail
> in compression from the tension of 48 spokes. This wouldn't be all
> that unusual, except for where the failure occurred: Not at the valve
> hole, but at the weld. The weld began to bulge and ripple, which was
> quite visible due to the machined finish traversing that area.
>
>
> Chalo Colina
What was the tension of the right side spokes? I have built more than a
few tandem wheels with 48/40 and have not seen this problem.
daveornee
6106
David Ornee, Western Springs, IL
--
daveornee
jim beam
> jim beam wrote:
>
>> and don't forget, rim alloys have changed over time. some are more
>> susceptible to corrosion than others, hence the need to anodize.
>
>
> What do they use now? I thought 6061 was the standard choice for rims.
>
something they call "maxtal" on the higher end. not sure what that's
equivalent to. these are generally Al/Mg/Zn/Si alloys. fwiu, old style
rims are predominantly 2000 series alloys which are basically Al/Cu.
dvt
From MIL-HDBK-5H, 1 December 1998, MILITARY HANDBOOK, METALLIC
MATERIALS AND ELEMENTS FOR AEROSPACE VEHICLE STRUCTURES:
"The high-strength heat treatable wrought aluminum alloys in certain
tempers are susceptible to stress-corrosion cracking, depending upon
product, section size, direction and magnitude of stress. These
alloys include 2014, 2025, 2618, 7075, 7150, 7175, and 7475 in the
T6-type tempers and 2014, 2024, 2124, and 2219 in the T3 and T4-type
tempers."
It doesn't mention 6000 series aluminum as having a problem with SCC.
All of the 6000 series alloys mentioned in the book (6013, 6061, and
6151) get high scores for SCC and corrosion resistance.
Although it isn't explicitly stated, I think the implication is that
6000 series aluminum is quite resistant to SCC. So if the MA-3 is made
with 6106 alloy, SCC is probably not the reason for the cracking. And if
older rims used 2000 series alloy, which are more prone to SCC than the
6000 series alloys, then it seems like the old timers would have had
more trouble with cracking.
Bill Sornson
10 months from now, Chalo and/or the D'oh Boy will snipe that you're a 'net
Nazi for that. (Never mind that you're right, of course.)
Bill "oops I forgot -- you're not conservative so you'll get a pass" S.
PS: "JESUS"?!? Are you allowed to say that?!?
Art Harris
> Mavic MA40 CD Road Rim
> These won't last long!
I had the same reaction when I read that in Nashbar: Truth in
advertising!
Art Harris
41
dvt wrote:
> jim beam wrote:
> > dvt wrote:
> >> jim beam wrote:
>
> >>> and don't forget, rim alloys have changed over time. some are more
> >>> susceptible to corrosion than others, hence the need to anodize.
>
> >> What do they use now? I thought 6061 was the standard choice for rims.
>
> > don't know what everyone uses. mavic use 6106 on lower end stuff and
> > something they call "maxtal" on the higher end. not sure what that's
> > rims are predominantly 2000 series alloys which are basically Al/Cu.
>
> From MIL-HDBK-5H, 1 December 1998, MILITARY HANDBOOK, METALLIC
> MATERIALS AND ELEMENTS FOR AEROSPACE VEHICLE STRUCTURES:
>
> "The high-strength heat treatable wrought aluminum alloys in certain
> tempers are susceptible to stress-corrosion cracking, depending upon
> product, section size, direction and magnitude of stress. These
> alloys include 2014, 2025, 2618, 7075, 7150, 7175, and 7475 in the
> T6-type tempers and 2014, 2024, 2124, and 2219 in the T3 and T4-type
> tempers."
>
> It doesn't mention 6000 series aluminum as having a problem with SCC.
> All of the 6000 series alloys mentioned in the book (6013, 6061, and
>
> Although it isn't explicitly stated, I think the implication is that
> 6000 series aluminum is quite resistant to SCC. So if the MA-3 is made
> with 6106 alloy, SCC is probably not the reason for the cracking. And if
> 6000 series alloys, then it seems like the old timers would have had
> more trouble with cracking.
What's this, you're providing proof that Mr. "jim beam" doesn't know
what he's talking about and is spreading incorrect information? How
completely shocking & unprecedented!!!!!!!!!!
dvt
[snip]
Please stop your trolling.
41
dvt wrote:
> 41 wrote:
> [snip]
>
> Please stop your trolling.
How could I be trolling? He (pretended to have) killfiled me long ago,
and now that Carl is gone there is no one to support his opinions. What
I do is provide an informative service to anyone who might be reading
him for the first time.P
dvt
> dvt wrote:
>>Please stop your trolling.
> How could I be trolling?
I don't believe your post added anything to the discussion at hand. It
was insulting or deragotory. In my book, that qualifies as a troll.
Chalo
Qui si parla Campagnolo wrote:
>
> >
> > I had a problem with a T519 rim recently where the rims started to fail
> > in compression from the tension of 48 spokes. This wouldn't be all
> > that unusual, except for where the failure occurred: Not at the valve
> > hole, but at the weld. The weld began to bulge and ripple, which was
> > quite visible due to the machined finish traversing that area.
>
> few tandem wheels with 48/40 and have not seen this problem.
I didn't measure it, but it was low enough that the left side spokes
wouldn't stay tight. And since it was a disc rear hub, the dish wasn't
even as extreme as most cassette hubs.
Chalo
Bill Sornson
> 41 wrote:
>> dvt wrote:
>>> Please stop your trolling.
>
>> How could I be trolling?
>
> I don't believe your post added anything to the discussion at hand. It
> was insulting or deragotory. In my book, that qualifies as a troll.
In other breaking news, leaves fell from trees today.
:o)
jim beam
and while i can tell you the principle, outline mechanisms and features
of scc, i don't have specific knowledge of these individual systems.
that said, let's summarize what we /do/ know.
1. old rims didn't crack.
2. modern rims do crack.
3. the cracking in modern rims appears to be intergranular, not
transgranular - as would be expected in an scc or a corrosion fatigue
cracking scenario. [ordinary fatigue as would be expected with
"anodizing induced" cracking would be transgranular.]
now, regarding what we don't know, let's read a quick synopsis:
http://www.key-to-metals.com/Article17.htm
this raises a couple of interesting questions, namely it specifically
mentions differences in scc behavior for 2000 series alloys depending on
section thickness, the thinner, the more scc resistant, as well as the
effect of stress orientation. rims aren't thick. [otoh, dura-ace
cranks are "dural", a 2000 series Al/Cu alloy, and scc doesn't appear to
much of a factor there.]
in addition to section thickness and stress orientation, it also cites
copper as an scc factor in both 6000 series alloys and 7000 series. i
don't know the exact composition of these alloys, but on 6106, there
appears to be considerable variation:
http://www.comalco.com/freedom.aspx?pid=525
so, who knows the specific formulation of mavic's "6106" or the exact
cracking mechanism. i know i don't.
returning to copper, i find its mention particularly interesting because
one of the cracked mavic 517's a friend gave me has the crack initiating
at the inner tube valve hole and there is a green crud on the fracture
surfaces. green is typical of copper salts and the brass of the valve
stem could easily have created a high copper chemical environment in
that region. i've kept the rim and, some day, may even get around to
having it analyzed. is this a factor for every rim? no - probably it's
just coincidence. at this point, microscopy is the way to be sure of
what's going on.
jim beam
my rear disk hubs [shimano xt] have exactly the same flange spacing as
the standard hubs.
41
dvt wrote:
> 41 wrote:
> > dvt wrote:
> >>Please stop your trolling.
>
> > How could I be trolling?
>
> I don't believe your post added anything to the discussion at hand. It
> was insulting or deragotory. In my book, that qualifies as a troll.
Please be accurate with your insulting terminology:
<http://www.pcmag.com/encyclopedia_term/0,2542,t=trolling&i=53181,00.asp>
<http://www.vikont.com/clients/glossary.htm#T>
That way, we can ensure a healthy environment for all.
As you will note, consistent with the correct definition, it's hard to
understand how I could be trolling. Beyond my previous explanation, one
has to add that, as it turns out, you were the only one to respond.
As for that, you may not believe it added to the discussion at hand.
That would be incorrect, for it put it into historical context..
Jay S. Hill
> Qui si parla Campagnolo <pe...@vecchios.com> wrote:
>
>>Warren Block wrote:
>>
>>>Michael Press <ja...@abc.net> wrote:
>>>
>>>>You still have the hubs? Get Sun CR-18 rims and build them up.
>>>
>>>For those of us with otherwise-good wheels with MA3 rims:
>>>
>>>Is there a decent, easy-to-get rim with the same ERD (607.5mm) as the
>>>MA3?
>>
MA3 & used existing hub & spokes).
Luke
<david....@ptd.net> wrote:
<snip>
> But most
> riders I see on group rides have these name-brand fancy-ass wheels. One
> guy last Sunday had wheels with 3 flanges -- and even with an extra flange
> they didn't have a full complement of spokes. Go figure.
I thought this was a typo! A little googling and this was the result:
http://www.fullspeedahead.com/fly.aspx?layout=product&taxid=49
I suppose it's only a matter of time before a 4 flange wheel hits the
market....
Luke
dvt
> let's summarize what we /do/ know.
>
> 1. old rims didn't crack.
>
> 2. modern rims do crack.
>
> 3. the cracking in modern rims appears to be intergranular, not
> transgranular - as would be expected in an scc or a corrosion fatigue
> cracking scenario. [ordinary fatigue as would be expected with
> "anodizing induced" cracking would be transgranular.]
Good summary. I can't say that your statement 3 is correct. I haven't
seen enough cracked rims.
> now, regarding what we don't know, let's read a quick synopsis:
> http://www.key-to-metals.com/Article17.htm
That reference says that "the service record of 6xxx alloys shows no
reported cases of SCC. In laboratory tests, however, at high stresses
and in aggressive solutions, cracking has been demonstrated in 6xxx
alloys of particularly high alloy content, containing silicon in excess
of the Mg2Si ratio and/or high percentages of copper."
I don't think a bike rim is subjected to "high stresses and aggressive
solutions." Maybe high stresses, but not particularly aggressive solutions.
> in addition to section thickness and stress orientation, it also cites
> copper as an scc factor in both 6000 series alloys and 7000 series.
Put in the context of the full quote including "aggressive solutions"
abd 6000 series alloys, I don't think it's relevant to the discussion.
> so, who knows the specific formulation of mavic's "6106" or the exact
> cracking mechanism. i know i don't.
Nor do I.
I looked at an MA-2 and an MA-3 this morning. They are both labeled as
6106 Al. If we posit that the MA-3 is more crack-prone than the MA-2,
and they both use 6106 alloy, which is not prone to SCC, I'd say that
SCC is probably not the cause of those cracks.
Andreas Oehler
>
>I don't think a bike rim is subjected to "high stresses and aggressive
>solutions." Maybe high stresses, but not particularly aggressive solutions.
Wet salted roads are very aggressive against "naked" aluminium alloys.
Together with electrochemical processes around spoke nipples and eylets
you can see the rims suffering from week to week.
Andreas - first snow flakes today here in southern Germany...
jim beam
> jim beam wrote:
>
>> let's summarize what we /do/ know.
>>
>> 1. old rims didn't crack.
>>
>> 2. modern rims do crack.
>>
>> 3. the cracking in modern rims appears to be intergranular, not
>> transgranular - as would be expected in an scc or a corrosion fatigue
>> cracking scenario. [ordinary fatigue as would be expected with
>> "anodizing induced" cracking would be transgranular.]
>
>
> Good summary. I can't say that your statement 3 is correct. I haven't
> seen enough cracked rims.
>
>> now, regarding what we don't know, let's read a quick synopsis:
>> http://www.key-to-metals.com/Article17.htm
>
>
> That reference says that "the service record of 6xxx alloys shows no
> reported cases of SCC. In laboratory tests, however, at high stresses
> and in aggressive solutions, cracking has been demonstrated in 6xxx
> alloys of particularly high alloy content, containing silicon in excess
> of the Mg2Si ratio and/or high percentages of copper."
>
> I don't think a bike rim is subjected to "high stresses and aggressive
> solutions." Maybe high stresses, but not particularly aggressive solutions.
people talk of local yielding at high spoke tensions. that's high
stress. andreas also mentions salts. salts going through a
wetting/drying cycle are very aggressive.
>
>> in addition to section thickness and stress orientation, it also cites
>> copper as an scc factor in both 6000 series alloys and 7000 series.
>
>
> Put in the context of the full quote including "aggressive solutions"
> abd 6000 series alloys, I don't think it's relevant to the discussion.
>
>> so, who knows the specific formulation of mavic's "6106" or the exact
>> cracking mechanism. i know i don't.
>
>
> Nor do I.
>
> I looked at an MA-2 and an MA-3 this morning. They are both labeled as
> 6106 Al.
ok.
> If we posit that the MA-3 is more crack-prone than the MA-2,
> and they both use 6106 alloy, which is not prone to SCC, I'd say that
> SCC is probably not the cause of those cracks.
>
maybe. if they are the same alloy composition [and that's not certain
given the variation possible within the 6106 designation] and are both
anodized, they're definitely /not/ the same mechanical construction. we
can also say those don't look/behave like fatigue cracks.
Peter Cole
> dvt wrote:
>> From MIL-HDBK-5H, 1 December 1998, MILITARY HANDBOOK, METALLIC
>> MATERIALS AND ELEMENTS FOR AEROSPACE VEHICLE STRUCTURES:
>>
>> "The high-strength heat treatable wrought aluminum alloys in certain
>> tempers are susceptible to stress-corrosion cracking, depending upon
>> product, section size, direction and magnitude of stress. These
>> alloys include 2014, 2025, 2618, 7075, 7150, 7175, and 7475 in the
>> T6-type tempers and 2014, 2024, 2124, and 2219 in the T3 and T4-type
>> tempers."
>>
>> It doesn't mention 6000 series aluminum as having a problem with SCC.
>> All of the 6000 series alloys mentioned in the book (6013, 6061, and
>> 6151) get high scores for SCC and corrosion resistance.
>>
>> Although it isn't explicitly stated, I think the implication is that
>> 6000 series aluminum is quite resistant to SCC. So if the MA-3 is made
>> with 6106 alloy, SCC is probably not the reason for the cracking. And
>> if older rims used 2000 series alloy, which are more prone to SCC than
>> the 6000 series alloys, then it seems like the old timers would have
>> had more trouble with cracking.
>>
> at this point, i'm at my limit. i'm not in the metallurgy game any more
> and while i can tell you the principle, outline mechanisms and features
> of scc, i don't have specific knowledge of these individual systems.
> now, regarding what we don't know, let's read a quick synopsis:
> http://www.key-to-metals.com/Article17.htm
>
> this raises a couple of interesting questions, namely it specifically
> mentions differences in scc behavior for 2000 series alloys depending on
> section thickness, the thinner, the more scc resistant, as well as the
> effect of stress orientation. rims aren't thick. [otoh, dura-ace
> cranks are "dural", a 2000 series Al/Cu alloy, and scc doesn't appear to
> much of a factor there.]
It also says:
"6xxx Alloys. The service record of 6xxx alloys shows no reported cases
of SCC. In laboratory tests, however, at high stresses and in aggressive
solutions, cracking has been demonstrated in 6xxx alloys of particularly
high alloy content, containing silicon in excess of the Mg2Si ratio
and/or high percentages of copper."
> don't know the exact composition of these alloys, but on 6106, there
> appears to be considerable variation:
>
> http://www.comalco.com/freedom.aspx?pid=525
According to that article a max of between 0.1% and 0.25%. Doesn't seem
like a lot of copper, even worst-case.
> so, who knows the specific formulation of mavic's "6106" or the exact
> cracking mechanism. i know i don't.
The literature you cited, if anything, seems to eliminate SCC as a
culprit for increased cracking in the newer alloys.
My anecdotal experience is that the Mavic rims (2) that I have had crack
at the eyelet were not exposed to corrosive environments (road salt). I
have plenty of rims (Mavic and other) that have seen a lot of salty
miles that haven't failed that way.
Qui si parla Campagnolo
Ya think they mean they don't have a lot and no new ones are made? I
agree it's funny way to phrase it tho.
Warren Block
>> Warren Block wrote:
>>
>>For those of us with otherwise-good wheels with MA3 rims:
>>
>>Is there a decent, easy-to-get rim with the same ERD (607.5mm) as the
>>MA3?
>>
> Third & last time I'm posting this: Velocity Razor (I've replaced an
> MA3 & used existing hub & spokes).
Where did you get them, and how much were they?
--
Warren Block * Rapid City, South Dakota * USA
dvt
> Fri, 18 Nov 2005 07:29:01 -0500, dvt:
>>I don't think a bike rim is subjected to "high stresses and aggressive
>>solutions." Maybe high stresses, but not particularly aggressive solutions.
> Wet salted roads are very aggressive against "naked" aluminium alloys.
> Together with electrochemical processes around spoke nipples and eylets
> you can see the rims suffering from week to week.
I don't think that's what they meant by aggressive solutions, but since
I can't read minds... Yes, wet salted roads occur, but how much of a
bike rim's life is spent in that environment? Most bikes don't ever get
out in those conditions. Even if they do, we're talking about a small
fraction of their lifetime spent in those conditions.
I think "aggresive conditions" refer to things like pipes carrying
caustic materials, chlorine (i.e. around swimming pools), and maybe even
full time immersion in salt water. Not the occasional splash of salt
water as seen on bike rims.
I've seen old rims with the galvanic corrosion you mention around the
stainless eyelets. That galvanic corrosion is peanuts compared to the
aluminum parts I've seen that were immersed in seawater for a few weeks
without the benefit of a sacrificial anode. As I see it, the bike rim's
environment is pretty tame.
dvt
> dvt wrote:
>> If we posit that the MA-3 is more crack-prone than the MA-2, and they
>> both use 6106 alloy, which is not prone to SCC, I'd say that SCC is
>> probably not the cause of those cracks.
> maybe. if they are the same alloy composition [and that's not certain
> given the variation possible within the 6106 designation] and are both
> anodized, they're definitely /not/ the same mechanical construction.
What do you mean when you say the mechanical construction is different?
Do you mean they are a different shape, or are they produced using
different techniques?
As for shape, SCC in 2000 and 7000 series alloys have some dependence on
shape. I haven't seen any reference to shape being a factor in SCC and
6000 series alloys.
As for production techniques, I was under the impression that nearly all
rim types were extruded. If you're saying different production
techniques were used, can you tell me what they are? I haven't looked
for any relationship between SCC and production methods.
David L. Johnson
> I don't think that's what they meant by aggressive solutions, but since
> I can't read minds... Yes, wet salted roads occur, but how much of a
> bike rim's life is spent in that environment? Most bikes don't ever get
> out in those conditions. Even if they do, we're talking about a small
> fraction of their lifetime spent in those conditions.
Only for those who don't ride in the winter. Even after the snow has been
cleared away, there is often a lot of salt on the roads, which gets all
over the bike. Around here (Eastern PA) you'd have to avoid riding from
December to April to not get salt on the bike. No thanks.
> I think "aggresive conditions" refer to things like pipes carrying
> caustic materials, chlorine (i.e. around swimming pools), and maybe even
> full time immersion in salt water. Not the occasional splash of salt
> water as seen on bike rims.
You apparently don't live in the Northeast.
--
David L. Johnson
__o | I believe that the motion picture is destined to revolutionize
_`\(,_ | our educational system and that in a few years it will supplant
(_)/ (_) | largely, if not entirely, the use of textbooks -- Thomas
Edison, 1922
dvt
> On Fri, 18 Nov 2005 12:31:22 -0500, dvt wrote:
>>I don't think that's what they meant by aggressive solutions, but since
>>I can't read minds... Yes, wet salted roads occur, but how much of a
>>bike rim's life is spent in that environment? Most bikes don't ever get
>>out in those conditions. Even if they do, we're talking about a small
>>fraction of their lifetime spent in those conditions.
> Only for those who don't ride in the winter. Even after the snow has been
> cleared away, there is often a lot of salt on the roads, which gets all
> over the bike. Around here (Eastern PA) you'd have to avoid riding from
> December to April to not get salt on the bike. No thanks.
Let's assume you ride an hour a day Dec-Apr. On each of those rides,
your rim is completely wet during the entire ride. And let's say it
takes an hour for the bike to drip dry thereafter. That makes about 300
hours submerged per year. Out of 24*365 = 8760 hours per year, or
300/8760 = 3.4%. That's a gross overestimate and it's still a small
fraction.
And *even if* that qualifies as an aggressive environment, the revered
MA-2 rim uses the same alloy as the reviled MA-3. And 6000 series alloys
are resistant to SCC. There seems to be little chance of SCC being the
cause of cracking in the MA-3.
David L. Johnson
> Let's assume you ride an hour a day Dec-Apr. On each of those rides,
> your rim is completely wet during the entire ride. And let's say it
> takes an hour for the bike to drip dry thereafter. That makes about 300
> hours submerged per year. Out of 24*365 = 8760 hours per year, or
> 300/8760 = 3.4%. That's a gross overestimate and it's still a small
> fraction.
With that analysis tires shouldn't wear out either, since they are used
such a small fraction of their lifetime. But rims tend to spend a large
fraction of the winter in a salty state unless you clean the bike
carefully, which I don't. Since much of that time they are also dry, it
probably is not a problem.
All rims used on salted roads in climates with a significant snowfall will
have some corrosion problems. The worst effect I see is that the nipples
tend to get corroded to the eyelets. Usually, surface corrosion is minor.
>
> And *even if* that qualifies as an aggressive environment, the revered
> MA-2 rim uses the same alloy as the reviled MA-3. And 6000 series alloys
> are resistant to SCC. There seems to be little chance of SCC being the
> cause of cracking in the MA-3.
This I do agree with.
--
David L. Johnson
__o | "A foolish consistency is the hobgoblin of little minds, adored
_`\(,_ | by little statesmen and philosophers and divines." --Ralph Waldo
(_)/ (_) | Emerson