Repairing Carbon Fibre - Carbon Damage & Repair

Interesting, presume the replacement is still going to cost quite a large amount though?

I wouldn’t be stoked about it, no. I’d look to get professional advice before riding it again in anger.

.

A carbon repair dude

Unless it’s like a super pro amaze bike shop.

Is this what has happened?
https://youtu.be/9u4_Ep8JbY8

It's a common thing with those frames, it's a fucking stupid design, I sent one off to target composites and when I spoke to them about it they basically preempted the whole conversation because they've done a load of them. They'll fix it better than new and add some re-enforcement so it doesn't happen again. It should definitely bea warranty issue but the customer just money gunned it for a quick (about a month) fix. If you want to money gun it I can't recommend target enough, great people and all the repairs I've sent them look finished better than what they've replaced.

My guy caught the wrath of Manchester tram tracks.

.

In a fair and just world Cannondale should fix this for free because it's their ridiculous design that's caused it, there's nothing stopping the bumps on the forks smashing through bare carbon. It's not fit for purpose, however I don't know how much of a ball ache that would be to sort out.

In a fair and just world Cannondale should fix this for free because it's their ridiculous design that's caused it

Crashing caused it. That’s not a warranty issue. Stupid design or not

If you want perspective on the the lovely but obviously loaded guy I sorted out, when I told him it would take at least a month he went downstairs and dropped £3k on a domane.

I disagree, it's way too easy to fuck the frame with some over enthusiastic turning. The fact that the carbon guys have had to sort so many they can predict the exact problem from a vague description of a Cannondale a few months after they go on sale means they've done something wrong.

I know what you're saying. It's a dumb design.
There will be many people with broken frames but ultimately in riding conditions it doesn't break on its own. OP crashed, that's not a warranty issue.
I know full well that it only broke because of the design but warranties cover manufacturing defects, not damage caused by use outside of the intended, aka crashing

So. I know a chunk about this, as I had a similar experience.

1. Yes it’s a moronic design, sticking a metal bump stop in the headtube that uses raw carbon of the headtube as the stop material is staggeringly stupid.

2. There’s no harm in asking Cannondale for a warranty replacement, but it probably won’t work as you crashed it. I have a SSEvo which developed a crack in the headtube from the same issue, only I didn’t even need to crash it, the design is that crap, just from usual handling, hanging it up, loading onto a car and mechanics handling in a bike shop was enough over time for the stop pin to crack the headtube. As I hadn’t crashed it, Cdale replaced the frame for free, my understanding is that they realised it’s a shit design and are easy going with replacements - if you haven’t killed it by crashing-. So sorry there. You can try the crash replacement policy but it’s pointless, it’s only like 15%off RRP.

3. Cannondale realised this is a crap design and made a running manufacturing change. SSEvo frames produced in the season after, MY2021+ have a metal insert in the headtube to counter the stop pin.

4. So this is where I ask the dad question, you using such an expensive frame- was it insured?

Why would Cannondale need to know it was crashed? 🤔

Yeah. They ask for a statement from the bike shop you purchased from stating on good faith that it wasn’t crashed, including photos of the bike from all angles with closeups of the contact points- hoods, bars, cranks/pedals, derailleur, looking for signs of damage to determine if you’ve crashed it.

Oof, fair enough! Time to replace any damaged parts then...

.

If you want to be an awkward, and in this case right, customer, I reckon you've got a fair chance of getting it replaced, their design is shit and if they've changed it since because it was shit, there really should've been a recall. If you've got ~£500 spare, get it sent off to target composites but I really think Cannondale should be fixing this, there's no way it's not their fault, yes it happened in a crash but any other frame likely wouldn't have broken in the same way, that frame wouldn't have broken in the same way if modified like target do. I'd be very annoyed if I'd spent that amount of money on something that's just not made properly, but TBF I'd never buy a Cannondale anyway because they're always full of awkward designs choices and stupid proprietary parts, this is one of the few choices I'd say is worth a recall though.

Does your frame have the metal insert which is meant to protect against this issue as noted above? If yours is a 2021 frame it should be there and should be visible looking down when the fork is turned. Big yikes if the supposed "fix" is there and it still failed.

Sorry, it's the 2020 one

Any thoughts on how to repair this properly? I bought a second hand EPS derailleur but the seller didn’t make it clear that the cage has been previously repaired… looks alright but would prefer a more substantial fix

1 Attachment

Personally I'd 3D print a mould with the rough shape, build up CF + epoxy around the cage, press in the mould, and once its solid, i'd sand it back down to desired shape.

Cheers for the tip. Unfortunately I don’t have access to a 3D printer

Any chance of a couple more photos? I can't really work out what is goig ton with the connection between CF and steel or what the previous repair looks like.
It looks like it's be very simple to fix with just a layer or two of woven fabric and some laminating resin. However if you don't have to materials on hand, it could still be pricey. I'd imagine anyone doing carbon repairs regularly could fix it quick n cheap though.