Total Motorcycle Community Forums

Hey all,
Hoping someone pout there can point me in the right direction.

I am riding a 1983 CB550SC Nighthawk and would like to replace both the front brake and the clutch master cylinder(s).
I have no issues with either system right now but the inspection "window" on both is clouded over with age and have some scrapes etc from being dropped (not by me....yet )

Problem is I cannot find the complete unit for either an was wondering if I could replace the entire unit with one from another bike without replacing the entire braking (or clutch) system. I would love to be able to simply replace the cylinder and hook it into the existing brake (or clutch) system.

Is this possible?

Tx in advance for the help.
Waylander

Sure it is. Make sure you "bleed" the system to get the air out.

Yeah as long as it has the same size "banjo" bolt that fits into both they should fit right up. Your only problem I can think of that you might run into is mounting it so that the reservoirs are relatively close to level.
And like JohnJ said, make sure you flush the system with new brake fluid and bleed it so that you don't have any air. Air + brakes = bad.

Something to keep in mind is the diameter of the master cyl. pistons, both the stock and replacement one should be as close to the same size as possible. If the replacement is much bigger or smaller, braking power will be different. You could end up having less power on the caliper pistons, hurting braking power, or they could become grabby and prone to locking.

Check they MC piston sizes in both units before bolting it on.

Ther are 2 things that I can think of. 1 is to make sure that you get a master cylinder from a bike with the same number of front discs as yours. Yours has a single disc, so make sure that you get one from a bike with a single disc. The other thing is to make sure that you get one from a bike with the same handlebar diameter as yours (I think that yours has a 7/8" diameter bar, but double check). Otherwise the clamps won't fit.