Hi all,
I was riding fast with friends yesterday on the 2nd half of the A-23 STS and descended into a chasm of a hole at about 28 mph (I was toward the back of the line). Got a pinch flat, fixed it, and we were on our way and made our train. A great ride, with an actual double-rainbow at the end in Poughkeepsie.
Only later did I notice a big bulge in my Conti 4000 tires at the point of the flat (unusual for these tires, which are generally indestructable). And then only today did I notice that the rim itself was dented at the point of impact. Wow!
I looked at my bike repair books and didn't see anything on whether it's ok to continue to use a rim that is _very_ slightly bent (a ding, not a problem of it being out of true) or if the conventional wisdom is that you just need to replace the rim when this happens. I'm replacing the tire, which is backed by warranty.
Thanks, as always, for the help.
David
Rim needs to be replaced?
As usual, it is hard to diagnose anything over the internet, but realize that your tire bead seats under the rim. So, you are probably fine, but a small variation in the seal around the rim might leave you at more risk for a blowout. Do you want to think about that the next time you are flying downhill and building up heat every time you brake.
Also, a shot good enough to dent the rim might also cause some small damage at the spokes that you might not see until later. So, I would at least keep a close eye on it.
If it happend to me, I would consider myself lucky that I didn't crash and could ride home on it, and then take the chance to pick a new cool rim and have someone build me up a flashy new wheel! (If you have some kind of hard to repair botique wheel, this might not make you as happy)
David,
If it were anyone else, including myself, I might say, yeah, just hammer the rim until it looks smooth and keep riding.
But you like to ride fast, and descend very fast, so I think your cycling equipment should be in perfect condition.
If the ding is very small, there might not be any hidden damage at all, but how can we know? You hit a big pothole while riding at a good clip, so a close inspection is in order. Maybe an opinion at a first-rate shop would help? None of us on the message board can actually SEE the rim!
Finally, rims aren't all that expensive, and even if you end up replacing one that's still serviceable, so what?
"Is the ding a ""hop"" in the rim, or are the walls of the rim sort of flanged out? In either case, the decision to repair it or trash it is really based simply on the severity of the damage. I've repaired several pothole-flanged rims to the point where it's very difficult to tell they were ever damaged. Rims with a hop are ususally impossible to repair to perfection, but if it's minor (and you're sure that the clincher bead will still seat properly) it's generally not noticable when riding.
I'd be happy to take a look at it for you and tell you what I'd do . . .
--DvB"
Doug's got a good idea. If it is slightly flanged, one way to fix it is to put the braking surface of rim at the problem location on a block of hardwood and place another block of hardwood on top of the rim and give it a little tap with a hammer.
- Christian
Not for the faint of heart - protect the rim with cloth, clamp the vice-grips on, bend to your heart's content. Not gonna be like new, you understand, but definitely less lumpy under braking than before.
Very helpful replies, even though diverse. The ideas about repairing clarified for me just how small the bend is. It is so minor that I have trouble imagining improving the rim by any bending I'd do. Very slight. It's just that, as others have mentioned, I descend fast and even the smallest imperfection could have disasterous consequences. So maybe I'll use it as an excuse to get a new wheel, or new wheelset (so they match!). Any other replies are, of course, welcome. But thanks for the ones so far.
David
"I'd still like to see it, but given your response above (""so minor that I have trouble imagining improving the rim by any bending I'd do""), I'd very likely just live with it. I used to ride on a set of Mavic MA-40s -- a custom wheelset that I had built when I was 19 years old. Paid for them with summer-job money. I got a hop in one of them on perhaps their third day of existence. After taking the Lord's name in vain, I rode on them, trouble-free, for another 17 years (please don't do the math). I'm not saying that one should have a cavalier attitude about his equipment -- but perfection is almost impossible without an unlimited budget. Luckily, perfection is rarely necessary!
--DvB"
Cavalier attitude, check.
