Carbon Wheels - Worn Brake Tracks

dannbodge

I recently bought a pair of Cosine 45mm wheels from a guy on here.
So far they have been great and I really like them.

Last week I went out and got caught in the rain. When I got home I saw that both wheels were covered in a white powder/solution.
I assume that this was where the resin has been wearing away whilst braking in the wet (like aluminium rims shed black powder/liquid).

So the next day I cleaned them and upon inspection of the brake track they look like the pics below in places.

My question is how badly worn do these look?
I read that when you start to see the carbon weave that they are almost done.

I only weigh 70kgs, the bike is 8kg and I'm using the Cosine supplied Carbon pads. I've been very careful with how I brake on them so I don't create too much heat (not that I do much braking on my training routes)

Thanks!

noodleman

I guess every manufacturer will have differences in their rim technology and appearance but my Reynolds assaults didn't look like that until they had around 5000 miles on them. Shortly after that they delamimated on a decsent.

dannbodge

noodleman wrote:

I guess every manufacturer will have differences in their rim technology and appearance but my Reynolds assaults didn't look like that until they had around 5000 miles on them. Shortly after that they delamimated on a decsent.

Yeah that's my fear.

I'm a bit annoyed about it as I've only done 200 miles on them and barely touch the brakes.

nicklong

The only one which concerns me is the very last picture, are they dimples in the brake track? If it's smooth I wouldn't worry, most carbon rims have a specific layer over the brake track (eg basalt) and you will notice a change in the type of carbon once the brake track is worn. As I understand it, the brake track isn't structural per se.

cycleclinic

I think those rims are fine. You can get a few more miles from them. what wrong with you all.

When the rim is visibly worn (like the front on one of mine it gone a bit concave then retire it) your a long way of that. Delamination happen because the rim has overheated not because the rim has a bit of wear.

Pad choice is critical with carbon rims. change your pads. Experimentation will tell you which are best. Manufacturer supplied pads can be rubbish and pad recommendations won't help much unless that person has the same wheels and tested various pads.

thegreatdivide

Re ‘see the carbon weave and they’re done’ comment. Wherever you read that and whoever posted it, it’s total tosh. If that was the case, super high end wheels like Campagnolo Boras would be junk out of the box. They even have the resin layer completely removed from the brake track by laser to give better stopping power.

As cycleclinic posted above, these rims look fine. Make sure you’re using good pads and give the tracks a wipe down.

Matthewfalle

Those are fine - no probs a5 all. Just dirty.

Methinks, however, if you’re going to panic like this all the time then these wheels may not be for you,

First.Aspect

Looks to me that all the grey cack is brake pad dust, that the "speckled" parts of the rim are unworn and the scored parts nearest tp the tyre are what slightly worn looks like.

dannbodge

In that case then, I'll change my pads (I've got a few options as I bought different ones when I bought them) and just make sure I keep them clean etc.

Vino'sGhost

i think theyre farked. I'll buy them off you though for spares for a tenner. :evil: :evil: :evil: :evil:

drlodge

Malcolm (TCC) uses the Red Campagnolo brake pads for his carbon wheels, might be worth a try.

First.Aspect

drlodge wrote:

Malcolm (TCC) uses the Red Campagnolo brake pads for his carbon wheels, might be worth a try.

I think there is a factory somewhere making brake pads with various pots of coloured pigment, the employees of which routinely scan internet bicycle forums to amuse themselves at people theorising about the differences between them.

OP, why do you want to change your brake pads? They all wear out, and the idea is that they do so before your wheels. So the fact that they leave grey cack behind is really just a style choice, as opposed to yellow, green or red cack.

If you can't stop, then one or other or both of the rims or the pads are themselves cack, in which case by all means shop around.

imposter2.0

First Aspect wrote:

I think there is a factory somewhere making brake pads with various pots of coloured pigment, the employees of which routinely scan internet bicycle forums to amuse themselves at people theorising about the differences between them.

Please let this be true..