View Full Version : Brake tech question

08-03-2009, 8:00 PM
I am looking for a answer for my rear brake dillema. after I have been riding awhile my rear brake starts to periodically stick closed. After I tap the brake pedal it releases and is good for a little while. I paid a guy a couple of years ago to rebuild the master cylinder because he said that was the problem, but it still does it. I dont know if maybe the caliper needs rebuilt or sometimes I question as to whether or not he even put the rebuild kit in the master cylinder. It seems to only do it when the bike gets good and warm. Anyone out there ever had this problem? or maybe knows the fix.

08-03-2009, 8:10 PM
come on I need some help with this. dont let my thread die.

08-03-2009, 8:33 PM
Probably not the problem, but did you mess with / adjust / make a new brake actuating rod - the one that goes from your pedal into the m/c? I made one up a while back, ended up moving the lever around ever so slightly and the brake tried to lock up 15 minutes into a ride. If that's not it, rebuilds of the caliper and m/c are probably in order.

Good luck

08-03-2009, 11:35 PM
yeah dude pull it all apart and clean it up real good and rebuild it

08-04-2009, 12:00 AM
Just my opinion, but I'd buy a brake hone from your local auto parts & rebuild that caliper. Maybe the heat, I don't know, but in my experience a caliper will always go bad before a master cylinder.
Let us know.

08-04-2009, 12:47 AM
yup that just happened to me, a piston in the caliper stuck and viola no brakes, plus bent rotor, hanger, fucked pads, and a injured caliper. when the piston stuck it kept the pad on the rotor causing it to heat up and distort

08-04-2009, 7:51 AM
Thanks Guys that really helped I think I'm gonna tear into the caliper.

08-04-2009, 11:16 AM
rebuilding calipers is easy. Make sure all parts are very clean when re assembling. & no burrs
on the pistons. easy way to remove the pistons is a blast of compressed air through the
banjo fitting bore, but catch it before it shoots across the room, dont get brake
fluid in your face.

Make sure the pads are not binding, I sometime smooth out any rough edges on the outer
(metal) edges on the pads.

12-25-2012, 6:21 AM
Are you sure you've added the correct brake fluid? If you've mixed fluids it will cause all your rubber to swell. Even if you rebuild your calipers and master cylinder you need to swap out new brake lines because the rubber in the lines will overtime leach the wrong fluid back in.

12-25-2012, 1:15 PM
this thread is 3 years old. how in the hell do you people dig up this shit?!

12-25-2012, 1:28 PM

12-25-2012, 3:19 PM
Hope the guy hasn't been waiting all this time for an answer.

12-25-2012, 4:30 PM
Didn't even notice the date, it was on the first page of the main forum, just kind of assumed it was recent.

05-03-2013, 6:40 AM
Hope you didn't wait all this time
To ride!! ; )

Same exact problem!
10$ caliper rebuild!
Good luck-