I'm just a software guy from Sydney (absolutely no idea about materials sorry)and am looking for some expert advice regarding a carbon fibrebike frame. The downtube on the frame was smashed and the fibres broken. I read that basically trying to repair this would be useless, as the strength of carbon fibre is all about the continuity of the fibres and one can't just patch them up. Well, we found a place that said they could do it, and indeed they did something that looks like the tube was never broken (sorry but I don't know the exact process used). Since then, however, it seems like one has to work harder to generate the same speed. A professional cyclist we spoke to reckons that once carbon fibre is breached like this it would compromise the rider's ability to get full power through to the drive drain, because of unnoticeable flex at that point. I have no idea, so can anyone help??