Hi, i recently bought some used wheels(500 miles), the rims are alex rims at450 i believe. After a bit of riding iv noticed that when im braking at high speeds the brakes make a terrible scraping noise. Im not sure the two are related but on the braking surface there are some small bumps of metal all over the braking surface, i took a little sand paper and tried it on a small area and it appeared to reduce the problem would it be wise to sand down the whole rims?
Could anyone shed any light on my problem?
I tried my best to capture the bumps but this is the best i could do, http://img195.imageshack.us/img195/5004/1001964e.jpg they are much more prenounced than how they look.