Mavic MA-40 - Piece of Crap?

I got a flat on my bike's rear yesterday. So today while I had the rear wheel apart, I took it over
to my neighbor's for a minor truing. On the way back home with the wheel, I noted that the MA-40
rim is cracking in several places near where the sidewalls meet the other part of the rim. It looks
like the eyelet is being pulled toward the hub. This is like the 4th or 5th one of these rims to do
this to me.

In the past, I have taken the failed rims to a big local Mavic dealer and they have given me
replacement rims. I am pretty sure this was one of those replacements as it has the newer label. The
last time I went in, I said, "no way - no more MA-40's, give me the cheaper MA-2 instead" and they
did. I have yet to encounter this problem with the MA-2, now sadly no longer being made.

I have read in several places that the grey anodizing/hardening of these rims causes this to happen.
It seems to be a well known failure. This wheel was built in 1997 but has seen little use (when you
have 8 bikes, each gets little milage). There is brake wear on the sidewalls but not very much.

Is this a problem on other rims? Is there an easy way to know which to avoid in the
future? Thanks...

Sometimes hard annodized rims crack, but sometimes totally non-annodized rims crack too. I have experience with both.
The alloy, extruding, heat treating, and annodizing all make a difference. Rim finishing such as maching the sidewalls and working the surface(s) surrounding the eyelets make a difference as well.
I am not an engineer or metalurgist. I have had good experiences and bad with all manuafacturer's products. Your dealer has a relationship with his suppliers that provide for some coverage in case of difficulties or failures. Circumstances, including time, are what drives how each individual case is handled.
I think that there are three things that I know you can do:
1. Buy rims that fit the application, including riding situations, tire size/inflation, and rider weight.
2. Use crossed Double Butted spokes that are evenly tensioned.
3. Deal with a dealer that will support your reasonable expectations. You should understand ahead of time what is and isn't covered, and for how long.

__________________
David Ornee, Western Springs, IL USA

HAHAH!!!! WTF-ever! The MA-40 is a legendary high durability rim. Lots of people swear by them for their training wheels.

On Mon, 22 Dec 2003 18:43:55 GMT, David White
<whitedavidp@comcast.net> wrote:

>I got a flat on my bike's rear yesterday. So today while I had the rear wheel apart, I took it over
>to my neighbor's for a minor truing. On the way back home with the wheel, I noted that the MA-40
>rim is cracking in several places near where the sidewalls meet the other part of the rim. It looks
>like the eyelet is being pulled toward the hub. This is like the 4th or 5th one of these rims to do
>this to me.
>
>In the past, I have taken the failed rims to a big local Mavic dealer and they have given me
>replacement rims. I am pretty sure this was one of those replacements as it has the newer label.
>The last time I went in, I said, "no way - no more MA-40's, give me the cheaper MA-2 instead" and
>they did. I have yet to encounter this problem with the MA-2, now sadly no longer being made.
>
>I have read in several places that the grey anodizing/hardening of these rims causes this to
>happen. It seems to be a well known failure. This wheel was built in 1997 but has seen little use
>(when you have 8 bikes, each gets little milage). There is brake wear on the sidewalls but not
>very much.
>
>Is this a problem on other rims? Is there an easy way to know which to avoid in the future?
>Thanks...

This is the classic example of the bad effects of hard anodization. David Ornee's advice is good.
And if all else is equal, choose a non-hard anodized rim.

BaCardi <usenet-forum@cyclingforums.com> writes:

> David White wrote:
>
> > I got a flat on my bike's rear yesterday. So today while I had the rear wheel apart, I took it
> > over to my neighbor's for a minor truing. On the way back home with the wheel, I noted that
> > the MA-40 rim is cracking in several places near where the sidewalls meet the other part of
> > the rim. It looks like the eyelet is being pulled toward the hub. This is like the 4th or 5th
> > one of these rims to do this to me.
>
> > In the past, I have taken the failed rims to a big local Mavic dealer and they have given me
> > replacement rims. I am pretty sure this was one of those replacements as it has the newer
> > label. The last time I went in, I said, "no way - no more MA-40's, give me the cheaper MA-2
> > instead" and they did. I have yet to encounter this problem with the MA-2, now sadly no longer
> > being made.

You have discovered on of the home truths about rims. Anodizing makes them more prone to cracking in
exactly the way you describe. This has been discussed many times in this newgroup, and thousands of
posts on the subject are available via Google and don't bear repeating here.

> > I have read in several places that the grey anodizing/hardening of these rims causes this to
> > happen. It seems to be a well known failure. This wheel was built in 1997 but has seen little
> > use (when you have 8 bikes, each gets little milage). There is brake wear on the sidewalls but
> > not very much.

Anodized rims frequently fail by cracking long before they wear out from braking. This is probably
not much of a problem if you're 120 lbs and ride 36 spoke wheels. If you're 215 lbs and ride 32
spoke wheels, you'll see this problem more often.

> > Is this a problem on other rims? Is there an easy way to know which to avoid in the future?
> > Thanks...

Avoid anodized rims. Well, good luck, there aren't any non-anodized rims on the (after)market to my
knowledge except possibly the Torelli Master, and reports conflict on that rim.

> HAHAH!!!! WTF-ever! The MA-40 is a legendary high durability rim. Lots of people swear by them for
> their training wheels.

Swear at them, perhaps. The MA-40 was a dog. The MA-2 was a great rim, the best Mavic ever made for
general use. David's post is far more accurate that your pathetic attempt to ridicule him.

Tim McNamara <timmcn@bitstream.net> wrote:
: Avoid anodized rims. Well, good luck, there aren't any non-anodized rims on the (after)market to
: my knowledge except possibly the Torelli Master, and reports conflict on that rim.

several of the velocity deep-v rims are powder coated. hopefully they weren't annodized first.
--
david reuteler reuteler@visi.com

David,

I have had the same problem on other anodized rims. In the case of my bike they were the rims that
TREK made or had made for several years. They would crack at the nipples and on the braking surface.
It turns out that someone had decided a light weight rim would work ok and then decided to make it
lighter and lighter and, well you get the idea. There is a point where it just ain't gonna work. Add
to that matter that I am over 200 pounds and don't slow down on the hills. :-) I have a set of
Mavics that replaced that problem and they are on my second bike now. Just within the last year or
so I had to replace the rear rim as it also broke. But that was after five years of riding that
wheel. Previously I would replace the rims once a year. And it always seemed to happen the same week
of the year on the same organized ride on the same day of the week +- 1 day!

Try to find a Mavic that is not a light weight rim and give it a try. The rims I have are anodized
on the surface that the spokes penetrate but the braking surfaces are machined. I don't recall the
model number right at this time.

Al Butler ka0ies

David White writes:

> I got a flat on my bike's rear yesterday. So today while I had the rear wheel apart, I took it
> over to my neighbor's for a minor truing. On the way back home with the wheel, I noted that the
> MA-40 rim is cracking in several places near where the sidewalls meet the other part of the rim.
> It looks like the eyelet is being pulled toward the hub. This is like the 4th or 5th one of these
> rims to do this to me.

> In the past, I have taken the failed rims to a big local Mavic dealer and they have given me
> replacement rims. I am pretty sure this was one of those replacements as it has the newer label.
> The last time I went in, I said, "no way - no more MA-40's, give me the cheaper MA-2 instead" and
> they did. I have yet to encounter this problem with the MA-2, now sadly no longer being made.

> I have read in several places that the grey anodizing/hardening of these rims causes this to
> happen. It seems to be a well known failure. This wheel was built in 1997 but has seen little use
> (when you have 8 bikes, each gets little mileage). There is brake wear on the sidewalls but not
> very much.

> Is this a problem on other rims? Is there an easy way to know which to avoid in the future?
> Thanks...

That hard anodizing causes cracking is a well understood phenomenon in aviation and has been
thoroughly documented. When the the hard anodizing fad first came along, about ten years ago, I
wrote extensively about it to no avail. Wrek.bike.tech folk repeated all the promotional garbage
that Mavic and others had written in defense of these rims. Meanwhile, I took a section of an MA-2
and an MA-40 with the same service life and had them sectioned and polished by the Alcan materials
lab that was available at the time. The MA-40 had failures as you describe and the cross sections
showed a crazed anodized surface with anodizing cracks propagating into the aluminum. The MA-2 had
none of this.

The worst rim failure of this type I saw had cracked circumferentially into the hollow chamber
leaving the spokes in the inner part and the tire on the outer part, the two parts being slightly
inter meshed and offset laterally. The rider was able to stop and call for a ride.

Although cosmetic anodizing is far less damaging, it also cracks and can in cases generate cracking
in the structure of the rim. The defense for this often given is that nearly all rims have some
manner of anodizing. Well that's not good, no matter who says so.

Jobst Brandt jobst.brandt@stanfordalumni.org

David Reuteler <reuteler@visi.com> writes:

> Tim McNamara <timmcn@bitstream.net> wrote:
>
> : Avoid anodized rims. Well, good luck, there aren't any non-anodized rims on the (after)market to
> : my knowledge except possibly the Torelli Master, and reports conflict on that rim.
>
> several of the velocity deep-v rims are powder coated. hopefully they weren't annodized first.

Well, it would be a waste of money to have done so.

Tim McNamara <timmcn@bitstream.net> wrote:
: David Reuteler <reuteler@visi.com> writes:
:> several of the velocity deep-v rims are powder coated. hopefully they weren't annodized first.
: Well, it would be a waste of money to have done so.

yea, you'd think that would prevent them for doing it. velocity's site *SEEMS* to explicitly state
when a rim is annodized but only list the colour when it's powdercoated. i know some of the deep-vs
are 'cause i use black deep-v rims. but it looks like at least some of the aerohead and razor rims
may also be powdercoated. the dyad (their touring rim) otoh appears to only be annodized.

the bontrager maverick has a powdercoat black 32-hole 700c version. they used to offer the fairlane
(its predecessor) in a 36-hole non annodized plain al but no longer. rivendell still sells them here

http://rivendellbicycles.com/webalog/wheels/18094.html

but their claim that they were made "just for us" is pure bunk. you can/could buy them at any trek
dealer. well, i did anyway. at freewheel in minneapolis in march of 2002 to be very specific.
--
david reuteler reuteler@visi.com

Tim McNamara writes:

>>> Avoid anodized rims. Well, good luck, there aren't any non-anodized rims on the (after)market to
>>> my knowledge except possibly the Torelli Master, and reports conflict on that rim.

>> several of the velocity deep-v rims are powder coated. hopefully they weren't anodized first.

> Well, it would be a waste of money to have done so.

Oh? If all that welding, machining and heat treatment isn't a huge waste. The MA-2 had none of these
features nor did the many Fiamme or Super Champion rims we rode before Mavic "invented" all these
processes. The MA-2 was still on the market at half the price of the "New" rims and the public
jumped on the more expensive ones.

Suckers!!!

Jobst Brandt jobst.brandt@stanfordalumni.org

david-<< I took it over to my neighbor's for a minor truing. On the way back home with the wheel, I
noted that the MA-40 rim is cracking in several places near where the sidewalls meet the other part
of the rim. >><BR><BR>

Not uncommon with this hard anodized, eyeleted rim.

david-<< Is this a problem on other rims? Is there an easy way to know which to avoid in the future?
>><BR><BR>

Don't use eyeleted hard anodized rims. Hard anodizing is marketing, nothing else.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

Oh and the seam welding and machining is a waste too? Give me a break

<groan> do we /have/ to go through all this again?

yes, anodizing can be a factor in fatigue and therefore rim cracking, but like all failure analysis,
we need to examine the whole picture and not focus on only one possible element. and it's not
sensible to hearken back to the "old days" of unanodized rims as if some despotic modern satan is
forcing us to eat our own children. for the most part, modern rim alloys are not as corrosion
resistant as their older brethren and for them, anodizing is an important part of protecting them
from the elements. for the record, the much fabled ma2 rim /was/ sold in silver anodized form. the
old mavic catalogs list silver anodized as well as "bright" among the available options. the ma2 i
own is definitely anodized, as have been all the ma2's i've seen at swap meets over the years.

getting back to the ma40, all modern rims are made from extruded aluminum. extruded aluminum,
depending on subsequent heat treatments, will usually have a strongly anisotropic microstructure.
[just like striped toothpaste coming out of a tube.] modern alloys are extruded much closer to their
ductility limits than some of the older ones. it's part of what makes them strong. if one sees
cracking following the extruded microstructure of a component, one /has/ to assume this
microstructure plays a significant role in failure. i believe the ma40 was a somewhat unsuccessful
attempt to push mavic's then-used alloy to its limits but it's failure paved the way for the "open"
rim series with a much superior alloy. the "open" series and their successors have not been as
failure prone, regardless of anodizing.

i'm not sure if it's still up, but there was a very illustrative photo that showed the effect of
microstructure on rim failure:

in ascii:

______
/ \ / \ ___| |
| |
\ /
\______/----

lousy drawing, but this is supposed to show the photo with the two cracks initiating at the eyelet.
this is important because if you look at an anodized rim with a magnifier, [silver 517 being a
classic example], you will see cracks in the anodizing *radiating* around the eyelet where it has
been punched through the rim. straight out of the factory. again, the anodizing cracks exactly
radiate around the spoke hole.

if anodizing were to be the sole cause of cracking, one would therefore expect to see the cracking
exactly axial with the lines of the cracked anodizing, as we see for the crack on the left. and
there would be no variation is this failure mode.

but on the right, this photo also showed cracking *tangential* to the spoke eyelet - i.e. /not/
following the radial cracks in the anodizing but following inherent flaws in the metal's extruded
microstructure.

one *cannot* therefore solely attribute cracking simply to anodizing, whether it be hard, silver,
black or purple. there don't seem to be any real micrographs on the net showing what extruded
material looks like, but this is a good representation:
http://www.stud.ntnu.no/~fjeldly/forming.html

just like a piece of wood is easy to split along its grain, so can be a faulty extrusion.

the ma40 was junk. just throw it away. no, most modern rims do not have this problem.

jb

David White wrote:
> I got a flat on my bike's rear yesterday. So today while I had the rear wheel apart, I took it
> over to my neighbor's for a minor truing. On the way back home with the wheel, I noted that the
> MA-40 rim is cracking in several places near where the sidewalls meet the other part of the rim.
> It looks like the eyelet is being pulled toward the hub. This is like the 4th or 5th one of these
> rims to do this to me.
>
> In the past, I have taken the failed rims to a big local Mavic dealer and they have given me
> replacement rims. I am pretty sure this was one of those replacements as it has the newer label.
> The last time I went in, I said, "no way - no more MA-40's, give me the cheaper MA-2 instead" and
> they did. I have yet to encounter this problem with the MA-2, now sadly no longer being made.
>
> I have read in several places that the grey anodizing/hardening of these rims causes this to
> happen. It seems to be a well known failure. This wheel was built in 1997 but has seen little use
> (when you have 8 bikes, each gets little milage). There is brake wear on the sidewalls but not
> very much.
>
> Is this a problem on other rims? Is there an easy way to know which to avoid in the future?
> Thanks...

Thanks to (almost) all who have replied. Sorry to have brought up a discussion which seems, by now,
to be old-hat. However, your responses have helped me understand the situation a bit better and have
given me new rim ideas. In addition to avoiding anodized rims (if possible - seems difficult) I will
certainly swap out the 14 guage straight spokes I have traditionally used on my 36 hole rims and
replace them with butted spokes. Happy holidays!