I purchased a 1978 CB750 a few weeks ago and I'm rebuilding the front disc brakes (there are two). I believe the forks and brakes were taken off a later model bike. Both of the brake pistons were pitted from some minor rusting and I'd like to replace them. The problem is that I don't know which pistons to order as replacements. They measure 38mm x 38mm and I can't find any in this size. Does any know where I can order this sized piston? Thanks.
