How has this happened? Is it dangerous?

[Sam Kennedy]

I was just washing my bike, where I noticed a small notch in the fork (carbon) where it looks like something has taken the coating away. I haven't crashed recently, and the bike hasn't been stressed, and it wasn't there last week.

I will take a photo once the rain has gone.

The only thing I can think of is either my wheel or tyre rubbing against the inside of the fork, but I always give my tyres a quick spin before setting off, to make sure nothing is rubbing.

How come I can just randomly get a notch taken out of the fork? Will I have to replace it?

 

[andy_wrx]

Need a photo I think.

You don't remember the tyre throwing a stone up or anything ?

 

[Moodyman]

I've got a few chips on the fork of my new bike. Winter riding and all those salt granules & brittled tarmac.

 

[Sam Kennedy]

Heres a pic:

I wont have to replace them will I? :'(
If I do I definitely wont use carbon again, if it just takes riding over 1 stone to break them.

The picture doesn't show it very well, but the notch is less than 1mm in depth.

 

[knonist]

Heres a pic:

I wont have to replace them will I? :'(
If I do I definitely wont use carbon again, if it just takes riding over 1 stone to break them.

The picture doesn't show it very well, but the notch is less than 1mm in depth.

It is fine. it is only the coating

 

[accountantpete]

It's the tyre rubbing against it. I can't see how you wouldn't have noticed it unless the wheel is flexing under heavy load - as when you are out of the saddle going uphill.

As knonist says,it's only the coating that has worn.

 

[Sam Kennedy]

I did notice a rubbing when I was sprinting, but I assumed it was the mud guard rubbing against the tyre, also it was only happened for the first 2 pedal revolutions then stopped.

 

[accountantpete]

I did notice a rubbing when I was sprinting, but I assumed it was the mud guard rubbing against the tyre, also it was only happened for the first 2 pedal revolutions then stopped.

Either there is play in the wheel hub or the spokes are too slack.

Whatever it is, it's allowing the wheel to flex under load.

It won't be the fork itself as alloy forks are quite strong in this dept.

 

[jamesxyz]

not long after i got my bike - the reflectors came off on a steep descent and chipped the back of the (carbon) forks badly - I was well cheesed off. It was only the paintwork and the carbon is visible now underneath. I've done over 3000 miles on it since, with no problems.

If you're nervous - take it to your LBS but carbon is a lot tougher than people think.

 

[accountantpete]

Whoops- didn't see the carbon forks bit. If they are cheap then it could be the forks themselves flexing. (It doesn't mean that they will break as a certain amount of flexing prevents this.)

 

[Sam Kennedy]

I've just noticed, even if the wheels could flex a ridiculous amount, the brake calipers would prevent the wheel from moving far enough for the tyre to rub on the forks.

One thing I have noticed is that my front wheel isn't dished correctly. It is brand new (has less than 300 miles on it). I can also flex the rim side to side, is this a manufacturing defect, or just wear and tear?