Dented seatstay on CAAD10 - ride it or not?

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shimmeD
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by shimmeD

That's huge, relatively.

Get warranty: bin it or use it for table-lamp, wall-clock etc.

If you let yourself get so attached to a bike, get something that's repairable eg steel or carbon.

For most of us, woohooo! time for a new bike. :D
Less is more.

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kbbpll
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by kbbpll

I'm curious if anyone thinks it was some stress imparted during the crash that caused it, as opposed to a true "dent" (i.e. impacting another object). It's so close to the bridge weld, and on the inside between the stay and downtube seems curious for impacting another object.

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Tinea Pedis
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by Tinea Pedis

shimmeD wrote:That's huge, relatively.

:lol:

Better tell a good quarter of the pro peloton that.

martinko
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by martinko

I would cheer on buying a new bike if my budget was ready for that :D

kbbpll, I was also curious how it got there. But my seatpost had got pushed into frame as much as it could have with the impact.
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Qman
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by Qman

That's a good point kbbpll. I was assuming the dent was due to a direct impact on the frame. With the knowledge that the seatpost was pushed in during the crash, and having taken another look at the photos, it is very likely that the "dent" is actually a compressive failure of the tube.

When a tube is loaded beyond its compressive maximum it will fail by buckling inward. This will either occur in the middle of a long unsupported span, or beside a relatively stiff point along the tube's length. The crease is just above the brake bridge weld, which is a stiff location.

When you crashed there was a large force upward on the rear wheel. Your body resisted this force through the seat. This resulted in a large compressive force in the seat stays, causing one of them to fail.

If the wheel survived the crash, then you can probably see that it doesn't sit straight in the frame anymore. One seat tube is shorter than the other.

I would definitely not ride that frame again. It has a fraction of its original strength and could completely collapse if you hit a bump.

shimmeD
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by shimmeD

Excellent point, Qman :up:
Less is more.

martinko
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by martinko

Yes, thank you. I didn't want to reveal everything but apparently it have made no good. :D

In fact, since I had crashed with front wheel and was then catapulted out of the bike and rolled on a road, the bike fell upside down, hitting the saddle and pushing the seatpost all the way down. At least, this is how it seems it happened.

bikewithnoname
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by bikewithnoname

I have a 1991 Cannondale mountain bike, it's dented to hell. I picked up a similar sized dent to yours mid way up the NDS seat stay about 8yrs ago, the bike is still absolutely fine and gets beasted on a regular basis.

Qman does however make a valid point. My dent was very clearly an impact dent (large piece of hillside), but if the tube was compressed in the crash it could simply fold up on you when you hit some pave.

Personally I'd still ride it; I very much doubt the rear triangle of a bike would catastrophically fail even if the seat stay snapped in that area. I've experienced a couple of broken pivot mounts on late 90's aluminium full suspension bikes in the past, both times there was just a loud bang and the rear wheel locking up (the failure of the steerer tube on my 1st gen Rock Shocks however was something VERY different and altogether more painful…)
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Zitter
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by Zitter

relevant thread, any thoughts on this dent? caad10 top tube about 1/3 tt length from the headtube

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thegunner
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by thegunner

i would ride it, a teammate of mine had a similar dent in the chainstay (and another in the TT to boot). she proceeded to win the state champs in her field on it ;)

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TwiggyTN
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by TwiggyTN

From what I see there, ride it. From the handlebar I assume?

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Zitter
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by Zitter

actually farther back than the handlebar, so not quite sure what hit it, but definitely blunt. I've been riding it for a couple months since it got those dents and I haven't noticed any change. just wanted to get some more thoughts

skinnywellfed
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by skinnywellfed

You might not think the fork steerer is damaged, better take a very close look.

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