Rear brake sticking

[FJRMaineiac]

Thanks all for your thoughts / suggestions. Gonna dig into it this weekend and see what I can find. Will report back on the other side.

Cover me, I going in!!

 

[wfooshee]

Something really bad has to happen for you to need a disc! Like running the pads all the way down and using the backing plates for brakes.
That said, if you did that, then, um, you sort of deserve the bill you got. . . . . Sorry.

Disc was heat warped but not marked up at all.

That sounds like an improperly torqued bolt or two, or dragging brakes building excessive heat. I've not heard of a warped rear on a bike in quite a while.

 

[WBill]

Have you tried spraying the rotor and caliper with disc brake cleaner? Just asking, WBill

 

[FJRMaineiac]

Not yet, but that is on the agenda for this weekend. Hopefully that will do the trick. I'll report back with the results.

 

[FJRMaineiac]

Success :yahoo: !!!!

I am going to chalk up the cause of the problem to general crud. I removed the caliper from the bike (leaving the brake line connected) and confirmed that the mounting bolts were in good condition. The small rubber boots that keep the dust and dirt out were intact, and the lubricant was still on the sliding portion of the bolts. As recommended above, I thoroughly cleaned the caliper and piston with brake cleaner, paying particular attention to the piston. I could find no damage to the piston itself, but before flushing the brake fluid I tried several times to "extend" the piston and then press it back into the caliper. Using just my hands, I could compress the piston to a point (about 1/2 way) and then it would stop as if the brake line was getting plugged with something. I assume it was a small piece of debris. I then bled the brake, flushing good, clean brake fluid through a few times. I never saw any debris come out, but it either came out or dislodged itself from where ever it was hanging out. I hope it found the exit, otherwise I will get a chance to practice this exercise again.

Once the brakes had been thoroughly flushed and properly filled, I reassembled the brake and took it out for a test drive. The brake seems to be working like new again.

And before someone asks, yes, I took this opportunity to change the fluid in the front brakes as well. No sense in doing half the job.

Thanks all for your suggestions. I think this one is in the can.

 

[FuzzyRider]

Good news - now get out and ride.

 

[mcatrophy]

Success :yahoo: !!!!... and then it would stop as if the brake line was getting plugged with something. I assume it was a small piece of debris. I then bled the brake, flushing good, clean brake fluid through a few times. I never saw any debris come out, but it either came out or dislodged itself from where ever it was hanging out. I hope it found the exit, otherwise I will get a chance to practice this exercise again.

...

I think this one is in the can.

Good result.

You see, 100 year-old MG-B stories can still be valid, whatever the sanity of the story-teller :dribble: .