Hello All,

Noticed today that the wheel on my commuter - has a "nice" crack on both sides of spoke (see attached photo). Rim is 1 year old and has 4300 miles - a good percentage on the rough pot holed streets. Any guess on how many miles left on the wheel before the spoke pulls through?

Thanks,
Jim - Kirkland, WA

Since the rim has yielded the spoke is no longer under tension.
Your rim is very likely out of true now.
Stop riding this wheel and replace it.
You will save yourself a world of pain.

Enjoy

The rim is toast. Replace it asap.

'how may miles left?'

Zero!

(Sure it may go a few, but why risk life and limb for something like this)

Depends.

If you have a 50 mile out-and-back ride planned for Saturday, it will last about 25 miles.

If your commute includes a section of bad neighborhood, it will last until you get there.

It might last until halfway to work on the next cold, rainy day.

It isn't going to last much longer so there's no point in tempting any of the above. You are going to have to replace it pretty soon in any event.

Miles? How many feet to the next pot hole?

Hello All,

Thanks for the feedback - the wheel with cracked rim has been retired.

Interesting enough the spoke (with crack around it) still had tension, but after removing the tire & rim tape the cracks were big enough to let light into body of rim.

Thanks again,
Jim - Kirkland, WA

Your problem could have been caused by over tension. You should have your spokes tension-balanced by a professional to avoid this problem in the future.

The MA3 has a reputation, deserved or not, of cracking at the eyelets. Mavic has replaced it in 2006. I just built my brother a new rear wheel with his old Campy hub and an Ma3, and I hope this doesn't happen to him. He's only 160# though.

His old rim is crazily cracked - at almost every eyelet on the drive side, cracks are starting to propogate through the aluminum. But his old rim is an aero-profile rim, and cracks developing in that sort of rim don't "lift" away, the way that a box-section rim like the MA3 will do. Which means, my brother could ride this old rim for 1000 miles after cracks started, but with the MA3 (or the MA40, which I cracked this summer on my bike) you should replace it immediately.

it is caused by a faulty rim design. this rim is known for eylet cracking.

Well, it's both. You have to be pretty careful to not over-tension the MA3. More careful than lots of other rims. But it's possible to build up an MA3 with proper tension - you just have a narrower window of usable tensions than with lots of other rims.