Carbon scratches, to ride or not?

scblack

Leucocholic
I reckon ride it. Except the bits on the silver section, scratches are barely deeper than the paint.

I would ride it.
 

SummitFever

Eats Squid
Is that a groove in the bars from your stem? If so, you need to remove the sharp edge on the inside of your stem. That will be bad news for any bar (carbon or alu).

As for the scratches, there seems to be a common misconception with carbon fiber that it's a bit like glass - once you get a scratch it will auto-magically crack. The complete opposite is true. It's made up of a shedload of individual fibers so in order for something like bars to fail prematurely from a scratch, the scratch will need to be deep enough to have severed a sufficient proportion of the fibers to put the bar strength below the force you're going to put through it.
 

Hellyeah

Likes Bikes and Dirt
I'd be more worried about that bit that looks like someone has run a pipe cutter the whole way around them, or is that just in the protective film?
That’s just from the stem, the deepest scratch is in the gold paint
No fibres but my finger nail definitely rests nicely inside scratch/gouge
 

Flow-Rider

Burner
How did you do it, did you hit something at a good speed or the bike fell over and rubbed on something ? If it's had a good hard hit it might have fractures in it that you can't see.
 

pink poodle

気が狂っている男
Haven't you guys seen speed grooves before? Aerodynamic improvements are huge!

That’s the problem poodles, if there’s a huck to be had I’m there
Well then...the streets are brutal - stairs, huck to flat, mistimed gutter, unexpected pot hole...if you were just cruising xc laps on it (given the intention of such a bar) it would probably be fine. But who wants to have a bar snap halfway down a set of 12 stairs or in the middle of a rock garden?
 

beeb

Dr. Beebenson, PhD HA, ST, Offset (hons)
Is that a groove in the bars from your stem? If so, you need to remove the sharp edge on the inside of your stem. That will be bad news for any bar (carbon or alu).
They have a clear grip compound applied over where the stem clamps, it just forms ribs around where the stem has been campled down and pushed the material out a little. I have one set with a few different stem clamp patterns on it, nothing to be worried about.

As for the scratches, there seems to be a common misconception with carbon fiber that it's a bit like glass - once you get a scratch it will auto-magically crack. The complete opposite is true. It's made up of a shedload of individual fibers so in order for something like bars to fail prematurely from a scratch, the scratch will need to be deep enough to have severed a sufficient proportion of the fibers to put the bar strength below the force you're going to put through it.
I think the risk is that where it has sharp edges on the damage, through the clear coat. It can lead to cracking or delamination of the fibre construction. [EDITED - because I was wrong]

My guess is, it would probably be okay, at least for a while. Closely monitor for the first few rides to make sure nothing is developing, then relax the inspection schedule if nothing occurs. (And I agree with @The Duckmeister - it won't just shear off in your hands, it'll either give some warning or you'd be doing something that would likely snap the bars anyway regardless of existing damage...)
 
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Flow-Rider

Burner
Speed crash at boomerang
Ride at own risk :D

My guess is, it would probably be okay, at least for a while. Closely monitor for the first few rides to make sure nothing is developing, then relax the inspection schedule if nothing occurs. (And I agree with @The Duckmeister - it won't just shear off in your hands, it'll either give some warning or you'd be doing something that would likely snap the bars anyway regardless of existing damage...)
 

pink poodle

気が狂っている男
It won't snap, it'll turn into a noodle and give ample opportunity to pull up safely.
That's going to depend what your doing when it gives out. I'm talking along the lines of riding as per pics, thus my suggestion of xc use as ok.

I haven't snapped carbon bike parts. I've snapped (and seen snap) carbon fishing gear and gold clubs. Depending where in the rod it snaps the outcome can be a clean break (such as the thin sensitive tip), a messy mesh Web like tennis rackets often do (in the meaty section near the butt), or an outright explosive mess like busting a golf ball (this while shop guy was trying to make the rod a circle). The golf club, well the head came clean off and went flying.

Why are there no carbon cricket bats?
 

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