Falling over on carbon frame bike -- likely to cause damage?

Question

As per my last post, I'm learning how to use clipless shoes.  First 3 days of practice went fine, but on the 4th I came to a stop and couldn't get my foot out in time -- in truth, I got  one foot out, but the bike fell the other way. So I and the bike tipped over to my left -- I caught myself with my hands, but the bike clattered to the ground with me astride it.
It's a carbon-frame Giant Revolt.  I see no visible damage to the frame, and I'll take it by the bike shop tomorrow, but since there's no visible damage I believe they'll say "it's fine".  Which hopefully it is.  But how worried should I be with this kind of crash?  I've read that when you crash a carbon frame, you should get it inspected professionally.  Does tipping over like this count as a crash?
I know that no-one knows the state of the frame, and without X-raying it -- which seems a lot to do -- there's no way to know for sure.  But then again "probably alright" doesn't feel very safe.
If every time I tip over while learning clipless means I could break the frame, this seems a possibly terribly expensive proposition.

Nathan Knutson · Accepted Answer

In practice, there is one thing I've seen enough to call it a pattern: aero/teardrop carbon seatstays and chainstays cracking near the joints after being flexed excessively during a crash. Some of these combine very light construction with a very flat joint in the side to side direction. Some frames like this you could probably break by falling over at low speed enough times. I'm mostly talking about the kind of tubes you'd see on a tri bike.
Most carbon bikes have nothing like the above vulnerability and, falling over at low speeds, realistically would only get damaged in a major single point impact to a tube. You could probably get that to happen if you fell on the wrong thing.

MaplePanda · Answer

Any lightweight road frame of any material can be dented very easily. As long as you don’t see a mark on the frame indicating that it touched the ground, there’s nothing to worry about.

juhist · Answer

If every time I tip over while learning clipless means I could break the frame, this seems a possibly terribly expensive proposition.

I agree, it is. There are few solutions:

Use a frame with a metallic frame and fork. Metals can only get damaged by bending, immediate cracking, or delayed fatigue cracking. The first two can be immediately observed and the third can be inspected on a dense schedule after a crash which you will end after you are satisfied that there will be no delayed fatigue cracks. This is different from carbon fiber which can get damaged in invisible ways and then suddenly fail "just riding along" due to the damage which would be visible only to either destructive testing or some kind of X ray machine.

Use a different bicycle for learning how to use clipless pedals. Preferably a bicycle that is as cheap as possible so you won't regret damaging the bicycle.

However, I find it strange that a clipless learner would crash. I have never crashed due to learning clipless pedals, yet have crashed few times due to other reasons. It is not a law of nature that every clipless learner has to crash. Several ways that could avoid crashing are:

If you are using clipless pedals with tension adjustment, set it to the lowest tension, but you'll probably want to adjust the tension up after your practicing is done
If you are using SPD pedals, use the multi-release cleat for practicing and when your practice is over and you can reliably unclip, only then switch to the proper single-release cleats
Try few times without moving how to clip and unclip. If you aren't moving, you probably won't crash. Only when you have learned the unclipping motion will you unclip in motion.

Falling over on carbon frame bike -- likely to cause damage?

3 Answers

Add your own answers!

Ask a Question