Carbon wheels and braking

BrandonS

I'm new to carbon wheels, so forgive me if this is completely dumb, but my back brake is squeeling really bad like a firework when it warms up; to the point people are looking in their rearview mirrors. Once it cools down it goes away. I haven't had it back out, but have since tightened the pivot bolt that goes through the frame, cleaned the rims with acetone, and used sand paper to clean off the pads.

I set the pads up by sticking a credit card between the pad and wheel on the side that faces the back of the bike to give them toe. Is this an acceptable manner or should I leave them flat against the rim and tighten them. The pads are SwissSTops Yellow that came with the wheels. I don't feel that I'm braking exceptionally hard or dragging my brags. At least not more so than than someone that would be more justifiable in running these wheels (aka not recreational riders like me). I don't believe I really braked at anything over mid 20's.

Judging from the pictures am I braking wrong and melting my pads or is this normal? Do I need to "wear in" the braking surface on new wheels?

BrandonA

I don't know about Easton rims and pads but I have Mavics. It is known that Mavic have a wearing in period during which the carbon rims need to get covered with a bit of break pad to become most efficient and stop the squeaking.

After a few 100 miles mine stopped making noises.

BrandonS

Do you leave all those streaks build up then on the braking surface?

sungod

cf rims do make more noise, hard to know if what you're getting is unusual without hearing it

if the pads are toed in and the surfaces clean, then give them a few rides and see if things improve, don't bother cleaning the pads/tracks unless you think they've become contaminated with oil/whatever and it's affecting braking

Calpol

I have read numerous times that those pads are particularly guilty of the squealing you mention. They are not recommended for that and and also the discoloration issue. The blue reynolds ones or the swisstop black prince seem to be the way to go with carbon rims.

herzog

Calpol wrote:

...The blue reynolds ones ...

Seconded!

DKay

I use Swissstop Yellows too and get crazy loud squeeling on hard braking on my carbon wheels. The rims and pads are clean and toed-in. Makes no difference.

drlodge

I'm using Swisstop yellow on my Planet-x/Gigantex tubular rims and they're completely silent.