Question on carbon damage from dropped chain

[Bostic]

A few months ago while downshifting and getting ready to tackle a steep climb the chain went too far over and got wedged in real good between the frame and the chain ring. This was while going from the 39t to the 30t. I've dropped chains before but not like this. It took some effort (and cursing) to un-wedge it and get it back on to the 30t ring. It's a Pedal Force CG2 purchased when they were offering it initially through a group buy. I stripped it down and it's been sitting in the garage since then. Some days I do miss riding a 16lb bike, how bad does it look? I had it built up with an Ultegra triple with the Wheels Manufacturing BB30 adapters.

http://imagizer.imageshack.us/v2/1280x1024q90/908/JhDivH.jpg

http://imagizer.imageshack.us/v2/1280x1024q90/537/3dqLdE.jpg

[Caballero]

Doesn't look to be structural just cosmetic from what I see.

[bdawe]

Ride it, Nancy!

[eBAUMANN]

Ride it, Nancy!

what he said haha

id ride that sucker without a moments hesitation.

throw a little nail polish on there if you must and its good to go!

[Louis]

I'd ride it.

I bet the area's designed by stiffness, not stress, so stress-wise you probably have lots of extra material. That means that even if you do have structural damage, it's unlikely to get worse.

[fogrider]

it's fine. back in the early days, some frames took a beating there. Trek put a protective titanium plate at the chainstay because the chain would get jammed between the chainring and the chainstay and that could do enough damage. but what this looks like is just some cosmetic scratches.

[Dead Man]

all of the above, plus... ahve you ever watched them build these things? There's so much composite built up right there you could do that another 10 tens before you weakened it any

[oldpotatoe]

Ride it, listen for strange sounds or creaks. Inspect occasionally. It's not going to break and hurt you, down there. I had a customer who was riding a bike where the seat tube, by the BB, was broken completely, all the way around..asking about a 'noise' when he rode it.

[nooneline]

It's always hard to tell from a photo but it does look possible that that damage has gone beyond the clearcoat and to the carbon itself.

If you were to take this to a carbon repair person, they would do the carbon version of putting a piece of duct tape over it, and it would almost certainly cost you well under $100.

[ergott]

Couldn't hurt to lay some epoxy over the unfinished carbon to protect it and prevent any further delamination.

[Bostic]

Thank you for the replies everyone. The first picture, there a small ding that is deeper than the rest. I'm going to go ahead and do a clear nail polish job on the areas then build 'er back up.

[lhuerta]

ride it....looks like clear coat and a bit of the carbon layer, but remember that the BB areas is where you will find the thickest layup of carbon.

More importantly, in order to avoid future chain suck damage, check your chain for wear; check your chainrings for wear or bent teeth. In order to avoid chain drop damage, adjust your front der properly; spend $15 on best insurance policy you will buy and get a chain catcher. Lastly, coat the damage with some clear nail polish, then get some Lizard Skins carbon tape and apply behind your chainrings in the areas that are subject to chain drop/suck damage.

[RedRider]

I'll second the chaincatcher suggestion. We suggest installing them on all carbon frames regardless of the components used.
K-Edge comes in a couple models and a few colors.

[mrogulja]

what he said haha

id ride that sucker without a moments hesitation.

throw a little nail polish on there if you must and its good to go!

not nail polish but clear epoxy glue...a thin coat on lightly sanded area will create a permanent cover

[David Kirk]

Paging Nick Crumpton!

Dave

[Peter P.]

Ride it, Nancy!

THAT was funny!

[Louis]

I wouldn't bother trying to build it back up to the same thickness as the surrounding material. Whatever you put there won't be nearly as strong as the original CF material, of which you likely have plenty as it is. Plus there's no need to do it for cosmetic reasons.

I'd just cover it with a few coats of protective paint (clear epoxy) and forget about it.

[Dead Man]

I wouldn't even bother with epoxy, unless you can get some unique industrial quality stuff- I used Loctite clear 5-minute to "repair" some torn carbon flakes in the rim of a wheel recently, and the stuff started the melt with just aceton, wiping down prior to gluing. I felt like the epoxy added basically zero strength, and isn't any more impervious than anything else you could put on it, so might as well use something that'll be easier to coat on well.

[Bostic]

I brushed some clear polish on the scuffs and built Nancy back up last week. Took her on my usual 200k ride up to San Francisco and back. Early start so I could get home in time to order pizza for the game. I still have to get a K-Edge road clamp on for 34.9.

http://imagizer.imageshack.us/v2/1024x768q90/661/9YcgDx.jpg

https://www.strava.com/activities/249278293

[Charles M]

Couldn't hurt to lay some epoxy over the unfinished carbon to protect it and prevent any further delamination.


Bingo.


Dont ride that without sealing it.

[thomashassler]

two part epoxy from Home Depot. Let it cure for 5 min, slap it on with a popsicle stick, and lay a couple layers of gaffers tape over it for the night. Peel the tape off in the AM, sand, and you're back to normal. I have done this on a few carbon BB shells and it's not a problem.

[FlashUNC]

Fwiw and at the expense of thread drift, I would not recommend a K-Edge. I'd more recommend something like a Dog Fang chain catcher.