Self repair a carbon fork

Discuss light weight issues concerning road bikes & parts.
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by LouisN

I know it's been discussed before, but can't find a specific subject for this.

After a crash last summer, the inside of my fork leg was chipped by some rider's shifter entering the front wheel.


I know it looks bad, but:

There is no soft spots, and the carbon doesn't sound cracked. Both legs still feels stiff .
OKAY, I just pulled on both legs with some force, and heard a "CRACK"....(daymn!!!)

So my question is, do some members here have self repaired some carbon parts with carbon prepreg carbon fabric, with success, using household tools only (cause I don't own a vacuum autoclave oven :lol: ) ?

I'd use the fork on one of the kids's bikes...if it's safe...

Louis :)

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by bikerjulio

Sure, patch it up.

It's only for a kid's bike.

What could go wrong?
There's sometimes a buggy.
How many drivers does a buggy have?


So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

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by justkeepedaling

Yeah, just do it. It's only your kids. Save a bit of money

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by liketoride

i read it like he would use his kids fork if it was safe. not put this fork on the kids bike. but he has the clear that up

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by LouisN

No, I'm serious. If I can save $100. but my kids end up at the hospital, it's still free, because here in Canada, we have public health insurance...

... :roll:

I'm questioning the real strenght of a household repair versus a "pro shop" repair. Lots of people here seem to be good at carbon repairs, even building carbon parts good for everyday use by cyclists, racers, etc...
There are hundreds of brand new expensive WW stuff here I wouldn't put on my kids's bikes :lol:

Louis :)

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by justkeepedaling

If you know what you're doing and have a vacuum bag, sure. If not, your kid may not be going to the hospital. May be the morgue...

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by prendrefeu

Unless you already have the equipment, consider:
-Cost of equipment (vaccum system, bag, safety equipment for yourself/family, tools for finishing it off) (it does not come out of the bag 'shiny perfect' it needs work after that part)
-Cost of materials (resins, cf layers, discs for finishing)
-Your hourly rate (no, seriously: consider how much your labor and efforts cost per hour)

... and not even considering the cost of failure (if that should happen)...

is it MORE or LESS than the cost of a new, or even a decent used, fork?
Exp001 || Other projects in the works.

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by Geoff

Louis, it just ain't worth it.

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by Antoine

it must be feasible but first take life insurance policies on the kids.

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by dj97223

I think the fork is the one place on a bike that I would not even think of "repairing" or "having repaired." Turn it into a truing stand for your front wheels?
“If you save your breath I feel a man like you can manage it. And if you don't manage it, you'll die. Only slowly, very slowly, old friend.”

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by konky

Maybe for me it's once bitten twice shy as a fork snapped on me once. I have a titanium plate in my face and was off work for 8 weeks. It happened when I was going uphill. If I had been going down hill I would have most likely been killed.

Unless you really know what you are doing I would recommend you don't DIY.

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by Causidicus

Last edited by Causidicus on Tue Jun 17, 2014 10:43 pm, edited 1 time in total.

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by Berk

In my opinion rather don't repair it and get a new one, or an used one that isn't damaged.

I repaired all kind of stuff, also some forks, but it just isn't worth in my opinion. For example the repair can cost +50eur, and for some more eur you can get a fork that isn't damaged..

Otherwise for that kind of damages it's probably the best way to cut the area where it's cracked, make a carbon insert that is glued inside the fork, and then restore the rest of the damaged area from the outside. But it has to be done with the right layup, right materials, process,...and it's quite a lot of work, in my opinion just not worth. In the end it has to be also painted, clearcoated, polished,... It's a different story if it would be a frame with broken seatstays, where the forces aren't that high, but for a fork it's just not worth, even less if you don't have experiences and if that would be some type of experiment. So in my opinion rather let that cracked fork and get a new one. Imagine your cracked fork here:
If it's still stiff while you press the droputs together that doesn't really mean anything..if it would fail, it would fail at the moment when there are big forces,..
Berk PROTO-TYPE Composites - Handmade In Slovenia
Berk Composites

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A little OT but not really----when I was 6 a handlebar stem snapped going down a REALLY big hill----I ended up skipping over a driveway and plunging into a deep ditch---breaking a collarbone.

My Dad's answer was to get the stem brazed back together---lol----I thought he loved me!!! :oops: ----anyway---never trusted that bike again.

Replace and rest assured. Money is only important if you're alive to spend it :thumbup:

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