Rear Master cylinder Issue

[jdmfreak1992]

Ok so I bought a rebuild kit for my 82 gs650 and I scored the inside of the master cylinder bad trying to get the seized piston out. I was wondering can I take some fine grit sand paper to it and remove a little material or is that going to case an issue with break pressure?

[Agemax]

how bad? can you show us a pic? you can get away with it if it is not too bad. if it is fairly deep and in the travel of the piston seal then it could well be beyond use.

[jdmfreak1992]

Its at the very top it's not to deep but I can catch my finger nail on it but thats the only part thats bad and it almost seems like the piston doesn't even go past that part.

[jdmfreak1992]

how bad? can you show us a pic? you can get away with it if it is not too bad. if it is fairly deep and in the travel of the piston seal then it could well be beyond use.

I bought some 1000 grit sand paper I'm going to try and sand it out and see what happens.

[jwhelan65]

Dosnt look to serious I think sanding it will take care of it.

[Maddevill]

It will be fine because the part where the piston seal rides is farther down the bore. Just make sure THAT part is smooth.