I hit a pothole and cracked my rear 404 tubular - about a half an inch into the brake track on one side of the rim, barely noticeable on the other. Has anybody ridden with a cracked carbon rim for, say, 100 miles?
I hit a pothole and cracked my rear 404 tubular - about a half an inch into the brake track on one side of the rim, barely noticeable on the other. Has anybody ridden with a cracked carbon rim for, say, 100 miles?
I’ve been racing on one since March, probably 1,000 miles or so (and 808). After I broke it I figured I had nothing to lose and starting using it for everything, bad pavement crits, weekday training races, etc. It’s the classic ‘Zipp brake track’ crack, about 1 cm in length, hairline crack. It’s a rear and I almost never use the rear brake, so the the ‘thumping’ doesn’t bother me. I think it’s totally safe to ride. I do keep an eye on it–it grew a little at first, then stopped.
The irony is that I’ve done down some really rough crits on it, and crashed on it pretty hard–and yet the only damage was the original crack! Now I can’t kill this thing even though I’m trying…
Thanks. I didn’t see how riding really loads the rim and would cause the crack to propagate. There’s a little concern that the tire sidewall will rub against the inside edge of the crack as it expands when under load. I’m only 165 lbs and I keep the pressure at around 120 psi.
Well, considering the Zipp has a spoked hub it probably won´t collapse on you like a full carbon wheel like say the infamous spinergy rev-x.
Thanks. I didn’t see how riding really loads the rim and would cause the crack to propagate. There’s a little concern that the tire sidewall will rub against the inside edge of the crack as it expands when under load. I’m only 165 lbs and I keep the pressure at around 120 psi.
I worried about the tire/rim thing a little, too–particularly since I run the tires around 85-90 psi (which probably helped cause the crack in the first place…). I’m racing around 135-140, FWIW–but I’ve literally beat the hell out of this thing since I knew it was broken, so I’m guessing you should be fine.
Well from the subject line I was going to ask if it is just a fairing crack. Apparently not the case. Have you ridden a cracked aluminum rim? If so the failure rate would probably be more rapid as the resin is more brittle than the Aluminium despite the fiber reinforcement. Replace it. Training wheels are cheap. Now because the “rough” number that you provide is so close to say 112 miles…I say DO NOT RACE ON IT! If You race and it fails and you take someone out they have every right to give you a sound ass kicking!
You are very perceptive about the IM and make a great point about the possiblity of taking someone out. I was prepared to deal with the risk if it was just me who suffered. Looks like I’ll need to find an alternative. Thanks.
I had the same thing happen to a rear 404 and rode if for 2 more years, including 2 IM’s. Still have it but went to clinchers.
Well from the subject line I was going to ask if it is just a fairing crack. Apparently not the case. Have you ridden a cracked aluminum rim? If so the failure rate would probably be more rapid as the resin is more brittle than the Aluminium despite the fiber reinforcement. Replace it. Training wheels are cheap. Now because the “rough” number that you provide is so close to say 112 miles…I say DO NOT RACE ON IT! If You race and it fails and you take someone out they have every right to give you a sound ass kicking!
according to the guy I talked to at Zipp, the brake track isn’t structural, it’s laminated onto the structural part of the rim. If you look at the crack, it’s pretty clear what he’s talking about. That’s why my crack expanded, and then stopped–just the brake track cracked. I don’t see any way the wheel would fail, and I certainly wouldn’t be riding it in crits and down 50mph descents if I can any concern.
The good news is that laminated braking surface actually does seem to work pretty well. The bad news is that it cracks pretty often.
Good man. How about Race day wheels? (Rentals) will they rent just one?. Training wheel with a disc cover? Now that is an excuse you could sell youself on. Rear is cracked, I need a disc!
Until it fails. Then you crash.
.
Given the non-structural thing and it not being a tubular maybe (if you epoxy it up) but I still say if something that you know was broken fails in a 140.6 and you take someone out, you deserve an ass whuppin. And I am sure some attorney could come up with a negligance suit for lost time etc. Probably wouldn’t stick but still a PIA. On the other hand, chances are if everyone stays out of the draft zone, it won’t be an issue.
Now there is a fun thread! “If your known to be broken (pre race) equipment fails, and you crash, taking out a wheelsucker in the process, who gets to kick who’s ass?”
Talk amoungst yourselves, I am beclempt.
there’s a plan…race day wheels…take out the insurance and give them back your broken wheel…genius.
Ala Ron White- You should be able to ride it “all the way to the scene of the accident”! : )~