Carbon Rims, Pusling and burning rubber?

[jonny jeez]

Hi, I've just bought some VO2 Race 50 carbon rims, which I am very happy with from general performance, smoothness and strength.

But.

I get a fair bit of pulsing on the front, which grabs a lot as it pulses. Whilst I appreciate carbon rims are not milled and are, as such, imperfect, can this pulsing lead to a skid in the wet...its very grabby.

Secondly, even at low speed, I get a burning rubber smell from my front...which also squeals at high speed heavy braking.

I'm not touching the tyre, have Correct Carbon pads fitted ...by the shop.

Should, I be taking the rims back?

 

[Yellow Saddle]

Carbon rims are terrible at braking and grabbing and pulsing are just some of the problems. If it pulses badly, take that particular wheel back and see if another one is better. It may not be. The reason for this is that carbon rims aren't extruded and machined like aluminium ones but come out of molds.

The smell is also a result of the way the brake pads are designed to work. Because carbon cannot conduct heat away from the brake pad like aluminium rims can, the pads get much hotter. If you use standard rubber pads in there they melt and smear. Carbon brake pads are made from a material that doesn't melt but sublimates and smokes. Carbon is a poor choice of rim material but fashion dictates that it won't go away.

 

[jonny jeez]

Thanks @Yellow Saddle

I thought as much but wanted to check before I went to kick up a stink.

The pads seem to dissolve to yellow dust as opposed wearing (although my Ali rims generate brake dust too, just not the same).

I'm glad as I really like the wheels, the noise they make, the increased speed and also the feel of them...just want to be sure they are ok really.

Glad I did now.

Thanks for your helo

 

[jowwy]

Thanks @Yellow Saddle

I thought as much but wanted to check before I went to kick up a stink.

The pads seem to dissolve to yellow dust as opposed wearing (although my Ali rims generate brake dust too, just not the same).

I'm glad as I really like the wheels, the noise they make, the increased speed and also the feel of them...just want to be sure they are ok really.

Glad I did now.

Thanks for your helo

I got away from that by using carbon rims with disc brakes, dont get any of those issues now

 

[jonny jeez]

I got away from that by using carbon rims with disc brakes, dont get any of those issues now

Yep...im a bit of a follower in that sense so am waiting until next year when the tour will doubtless all be sporting discs...then my n+1 will be on discs...much more favourable.

But right now, I just cant get beyond them looking somehow odd.

 

[jowwy]

Yep...im a bit of a follower in that sense so am waiting until next year when the tour will doubtless all be sporting discs...then my n+1 will be on discs...much more favourable.

But right now, I just cant get beyond them looking somehow odd.

I love them on my both my roadies........and no rim wear too, so carbon rims (unless you crash) will last and last

 

[jonny jeez]

I love them on my both my roadies........and no rim wear too, so carbon rims (unless you crash) will last and last

Actually, on that point. How much wear can I expect from carbon rims. It seems the pads do a lot of the "wearing" and, so far ...after about 100 miles...my rims look untouched.
Whenever I previously bought new Ali rims, they were marked after about 20 miles.

How may miles would you imagine a carbon rim will take before it "explodes" from wear.

You can tell my expectations are not high!

 

[jowwy]

Actually, on that point. How much wear can I expect from carbon rims. It seems the pads do a lot of the "wearing" and, so far ...after about 100 miles...my rims look untouched.
Whenever I previously bought new Ali rims, they were marked after about 20 miles.

How may miles would you imagine a carbon rim will take before it "explodes" from wear.

You can tell my expectations are not high!

To be honest i cant give any sort of answer to that as i only do around 3k miles a year and thats spread over 3 bikes

 

[Yellow Saddle]

Actually, on that point. How much wear can I expect from carbon rims. It seems the pads do a lot of the "wearing" and, so far ...after about 100 miles...my rims look untouched.
Whenever I previously bought new Ali rims, they were marked after about 20 miles.

How may miles would you imagine a carbon rim will take before it "explodes" from wear.

You can tell my expectations are not high!

They don't last very long. The weakest link is the brake track and that can wear out quickly, especially if you ride in gritty slush. How quick is quickly? It is subjective but much, much faster than aluminium.

 

[jonny jeez]

They don't last very long. The weakest link is the brake track and that can wear out quickly, especially if you ride in gritty slush. How quick is quickly? It is subjective but much, much faster than aluminium.

Blimey...half the life of Ali perhaps?