Just went out for a run and the bike felt as though it was tightening up, pulled the clutch and I came to a rather quick stop, the rear brake was locked on, disk glowing, stuck at the side of the road with basic tools I loosed the brake pipe to relieve the pressure and got it home. Now all is well and working without any adjustments. Any ideas you wise men. Steve
this is often caused by not having enough free play at the master cylinder pushrod and more likely in the summer* when the heat soaks into the fluid expanding enough to remove the little mechanical play that's there. From then on it's a catch 22 as all the expansion is directed at progressively locking the brake on. *but can be made worse by a very partially seized caliper. Sometimes giving the rear brake a good work-out (even this heat cycle may have helped as long as it hasn't permanently distorted anything) will be enough to free it off - I don't know if you are someone who uses yours regularly? Additionally - I think you said the disc was glowing? - it will now have a glaze on it unfortunately** At best you can flat off the surface with some rough aluminium oxide paper but at worst it could have changed in temper and may need replacing. ** ditto for the pads - if they were low anyway then best replace (but use these to confirm brake locking cured as you will wreck the next set) - if they had plenty of meat then see how dark and shiny the faces are and flat off with around 300/400 grade until lighter and matt-er face restored (the dust will be dark and carbon-like).
Thanks Chris, that makes sence, when l stopped the foot peddle was locked solid. That's why I had to loosen the hose to release the pressure. Steve
Very often the small orifice in the master cylinder gets blocked as the fluid has to return and it does not return back to the reservoir by the same route that it left. This orifice is small you may need to use a bristle from a wire brush. So in simple terms you have used your rear brake and let it off but the fluid can't get back so its still under pressure holding the brake on. The hole is called the recuperating orifice.
you saved me editing (again) Phil - had above happen on my 400SS this year (front brake). Another similar quirk can happen when the reservoir is too full and/or the reservoir air breather is blocked.
Can also happen (front) when after market levers a poorly fitted/adjusted. Usually the 'cheap' lever is blamed!
Happened to me twice, first time was right after the first service where the garage had done something to the adjustment on the brake pedal and it seized up after a couple of miles - pads were actually on fire and the paint burnt off the rim of the disc. Next time was many years later when I bought new rearsets/pedals and although I thought there was enough play the brake locked up after a few miles and again was very hot. I removed the pin that connects the pedal to the master cylinder at the roadside and then when I got home put a little more play in the system and it's been fine since. On the plus side it's the only 2 times the rear brake has actually worked...
