Master Cylinder Piston Help

I took my master cylinder off 72 commando, got a rebuild kit and now need your help. Is the piston re-useable oe do I need a new one? If not useable will I need to get the master cylinder sleeved also?
Thanks

brother, if you replace that piston and cylinder with a rebuilt, re-sleeved one, and a braided stainless line, you will ask yourself 'how come I didn't do this a long time ago?" My front brake is now really effective, the upgrade was worth the time and money, ten times over. I got mine from Rabers.
Cheers, Don

Size does matter. In the case of the stock master cylinder, smaller is better.

blipJC said:

I took my master cylinder off 72 commando, got a rebuild kit and now need your help. Is the piston re-useable oe do I need a new one? If not useable will I need to get the master cylinder sleeved also?
Thanks

Click to expand...

When I rebuilt my master cylinder I had a piston that was corroded like yours but the bore looked ok. Not being steel there was no rust.
I got a new piston and after struggling the new rubber seal on it (takes strong fingers!) put it back together and works fine.
However there is a strong opinion of a lot of board members that resleaving to a smaller diameter gives a stronger brake.

Since the whole system was drained of fluid I opted to use DOT 5 brake fluid to avoid corrosion problems internally and from spills on paint.
There is a previous thread that discusses the pros and cons of DOT5.

Bob

I wouldn't say that it's a strong opinion. It's a fact. The stock disc brake with the stock MC is awful. Sleeve the MC. No doubt.