Hi there help needed. I was riding down the motorway and applied rear brake to slow down as I just installed rear pads, lines and rotor and my brake just locked. I was going at 140 km so I skidded for nearly 50 Mt luckily I controlled the bike and had to wait 15 Min for it to cool so I could ride home.
When you installed the new pads did you take a wire brush to the retainer/guide pin? They get a build up of dust on them that causes drag. That drag can lead to the pads sticking in a position where they lightly rub the rotor, creating a lot of heat in the rotor. Touch the brakes, they make full contact, that heat is now dumped to the full system, brake fluid expands - and there you are.
I bet if you pull the pads now you'll find that one or both are worn at an angle not perpendicular to the backing.
I did not use a wire brush the pads where installed in the bike yesterday with new fluid ??
Got any free play at the lever?
Did you adjust the pedal position?
If the master cylinder piston is pushed in, it blocks the bleed port, and the system is sealed.
Then as the caliper heats up due to constant brake drag, the fluid expands, then more drag, hotter.....
Quote from: MoNsTer82 on March 28, 2012, 11:51:40 AM
I did not use a wire brush the pads where installed in the bike yesterday with new fluid ??
So inspect and clean that pin. Inspect the pads - they may be worn at and angle and therefore not usable. Follow speedDogs recommendations - if you adjusted the pedal position or the linkage from the pedal to the master you may have gone too far and blocked the fluid return.
yes I adjusted the linkage to the master I need to apply less pressure on the brake lever now. that could be the problem I will try and see if I can fix before taking it in to a garage, Thanks for your fast replies m8
Odds are that's your problem. There needs to be some bit of free play in the lever. A few mm of travel at the tip before the linkage beings to act on the brake master. Eliminate that free play... and you know what happens
I adjusted the rear master back to its position and for now all good just hope it doesn't happen to me again, I am bedding in new rotor and pads but have lost confidence with using the rear brake now.
It's a very simple system that you tweaked too much. Obviously you need to ensure that it won't act up again, but if you did bring it back to a point where it was before, with the proper free play then it should be just fine.
thanks a lot mate you have been very helpful [thumbsup]
No prob. Perhaps pack a small tool kit the next couple runs with the stuff needed to adjust the brake free play.
A while back I installed new levers on my 900 and over adjusted the free-play of the front brake and clutch. I was watching for it, so I pulled off as soon as I felt the brakes dragging and backed off on the plunger pin length and problem solved. But if I didn't have the tools I would have been stuck until it cooled like you.
lol that's exactly what I have done I put the smallest spanner I had and packed it under the seat [thumbsup] [beer]
Rear brake locked up on me twice after I installed rearsets ans messed with the plunger...bad move on my part.
Research and adjusted the free play/plunger...so far so good.
Btw...the the pressure switch installed sad panda [thumbsup]
Good to hear.