rear brakes

[xswilly]

decided to take bike for a little spin as the temps have warmed up for a few days here
bikes been sitting for 2 months, winter up here
pushed down on the rear brake and it went down about 1/2 way and stopped, then it felt like it pushed by a little
now the rear brake is dragging
looks like i need to take apart either the master or caliper
which one?? and what would i look for??
maybe a ridge of rust??
it can't be as simple as the sponge hole could it?

thanks xswilly

[TopCatGr58]

Hey Willy,

The shaft that the rear brake lever swivels on can get gunked up or rusted, and the return spring isn't that strong, so it might be just a matter of pulling the lever off, and cleaning and greasing the shaft and such.

But it might also be the MC, I'd try the lever first, then bleed the rear caliper and see what color/condition the fluid is, if dark brown or even grungy, then it's probably that way in the MC as well, and a tear down might be in order! But maybe even just a thorough flushing of the old fluid out of the MC and system would be enough! Like using a syringe or so to remove most of the old fluid out of the MC first, then refill with fresh, and bleed, bleed, bleed replacing the MC fluid of course as needed until it comes out clear!?
T.C.

[TucmanXJ]

Willy - T.C. has good tips.

Common XS problem: no grease at the rear pivot / brake lever bolt > inside. Remove the rear brake lever and clean all contact surfaces, apply good quality moly grease or white lube if you have it.

If not the above:
Remove rear m/c and see if its leaking ,check for brake fluid exiting around bottom rod / seal. Is the actuating piston / rod stuck in the bore? Next check the caliper pistons to see if they are cocked, rusted in their bores, have missing or torn O-ring seals etc.

Take a look at the brake pads, see if they show any signs of unusual wear, down on one side. Also a thorough cleaning can help in this area.

Good luck!

RJ

[xswilly]

thanks for the advice
i will start with the brake pedal,
i hope that is it
i hate to have to disasemble the master cylinder
but i have time, they are predicting 6 to 10 inches of snow monday, i knew the good weather couldn't last

[TucmanXJ]

Time for those winter projects to get under way ... like when I repaired the rear master cylinder.



Rob's super secret XS testing & development lab somewhere in the great southwest.

[randy]

xswilly,

My 79F has a grease fitting on the brake pedal. There's a black cap on the pivot end, underneath is the zerk fitting.

[xswilly]

sad to say it isn't the pedal
it travels up and down without sticking
and yup there is a greese fitting under the rubber cover
so i guess i'll try changing the fluid and bleeding and cleaning the sponge hole
tonight i blew 12 inches of snow
good thing is, it was light and fluffy