Expertus Opinus Needed

[techguy]

I disagree because carbon can fail without warning and I've witnessed a couple of crashed because of it. Carbon has a higher fatigue life than alu but when it fails it is catastophic, and in a way the hole may not get bigger and cracks may not visibly occur but the fact of the matter is that there has been a delamination of some degree of the layers. So a crack may spread on the inner layers and no-one would be any wiser till it fails.

[Johan Bornman]

I disagree because carbon can fail without warning and I've witnessed a couple of crashed because of it. Carbon has a higher fatigue life than alu but when it fails it is catastophic' date=' and in a way the hole may not get bigger and cracks may not visibly occur but the fact of the matter is that there has been a delamination of some degree of the layers. So a crack may spread on the inner layers and no-one would be any wiser till it fails.[/quote']

 

It would be of value to us if you could explain the nature of these crashes and their cause. I am particularly interested in the location of these holes in the frame and the mode of failure.

 

 

[Mr Mulebar]

I disagree because carbon can fail without warning and I've witnessed a couple of crashed because of it. Carbon has a higher fatigue life than alu but when it fails it is catastophic' date=' and in a way the hole may not get bigger and cracks may not visibly occur but the fact of the matter is that there has been a delamination of some degree of the layers. So a crack may spread on the inner layers and no-one would be any wiser till it fails.[/quote']

 

 

 

Techguy has a good point, if a stone was travelling at enough speed to puncture a hole in your down tube you can be sure that there has been separation of the fibers on the inside of the tube, which will weaken the frame. For your own peace of mind and safety replace the frame, insurance will cover it.... if you have it insured that is.

 

 

 

It's really good practice to use a clear vinyl protector on your carbon down tubes especially on carbon.

[Sean Badenhorst]

I'm not an expert in frame materials, but I'd get it checked by someone who is. Maybe email a couple of photos to SCOTT for an opinion. Robbie Powell is the Scott brand manager for SA: robbie@probike.co.za

 

On the bright side, here are carbon bikes in much worse condition than yours:

 

http://www.bustedcarbon.com/

 

 

 

[Hog_]

Am I the only one wondering how a road bike can have a hole knocked in it by a stone? Are you saying that the front tyre shot a stone up with enough velocity that it knocked a hole in the frame?

 

 

 

[techguy]

Keep in mind that a carbon frame can be as thin as 0.5mm in places especially on a road bike. So yes a stone can punch a hole in it. Now I'm not claiming to be a composites expert but I've done a couple of courses recently and put under enough stress any carbon will fail, a bicycle frame gets its strength from the tube shape and if that surface has been compromised then to leave it alone is risky, you could repair the hole/crack etc but remember that the modern epoxies used today can be stronger than the original materials so by repairing the hole/crack you could be allowing for stress risers to appear either side of the repair job. Having said that however, a repair would be better than leaving it alone.

[Cassie]

This being a road bike....i'd say go the insurance route!! It mmight be a differnt story if it was a MTB....i.e one expect stones to the a regular feature.

 

This would be an interesting test for Outsurance who, according to the dude that sold me bike insurance, something like this would be covered (even on a mountainbike)...noo problemo!

 

Good luck and keep us posted - certainly interesting!

 

[pedal menace]

Unfortunately no insurance...replacing a frame is no cheap exercise...prices have gone UP big time. I think a new CR-1 frame would probably go for close to R20K?

 

[shanejvv]

I agree with TechGuy.

 

We've had experience patching damaged carbon frames, mostly mountain bikes and all had much bigger holes than what you've got, very close to the head tube too.

 

All the bikes are still going fine, no troubles. Obviously, no guarantees are implied.

 

PM me if you want the details.