First off I've just joined this forum so hello. I bought a '79 CB750 a couple of months back and it's on my list to rebuild once I've completed a car I'm working as well.
The bike runs but does need some work. Particularly the front brakes. In Australia we had the dual disc front. The left side calliper has seized so I've taken the calliper off the disc so I can move the bike in and out of my garage while I work on other things.
Now the right hand side is starting to seize up. I've heard that this was a common occurrence on this bikes and was related to the fact that the standard pistons were chrome plated rather than being steel?
Either way ... I need to get some replacement pistons.
There seems to be a mixture of pistons for these units. The measurement on the one I've removed is 32mm on the inside and 37mm long/tall.
From what I've seen, all the front/rear pistons are the same from 77-80. Should measure 38mm tall by 35mm OD. Same part number front and rear. 21.00 each here in US. I need pistons for my 1980 CB750F and they are the same.