Barnman wrote:just a thought - It sounds like the pads are not releasing properly (calliper pistons sticking?) and then when you go for a ride, the friction on the disk causes it to heat up, expand and lock tight against the pads?
Here's a tip, wedge plastique into your brake caliper and well... you can imagine the rest! :laugh:
No more sticking rear brake! :silly:
"It is good to have an end to journey towards; but it is the journey that matters in the end."
That is the problem, haver cleaned all parts well and small test run seems that all is working will let you all know after I have tried to go for a decent run
Hi
tried all the things listed gave system a reall good clean and replace what i could, last night went for short 20 miles and and no real problems then in last mile looked down a saw a very nice bright glow from rear. Stopped and the rear brake disk was glowing red with heat. so had to wait half an hour before brake cooled down enough for me to ride tentatively last mile home.
It looks like I am gouing to have to buy whole new brake system caliper, pads, lines and master cylinder before I can get going again.
Thanks one and all for help and if any one knows where I can get the parts listed cheaply or compatable parts please let me know
Thanks
Had a speed read through this post so forgive me if I duplicate anything.
What's the fluid level like, as it sounds like an overfilling scenario to me.
Overfilled = No room for expansion = Brake being partially activated / drag?
I had a very similar hydraulic problem with a Ducati clutch, basically after fitting a Barnett racing clutch the unit was locking out after the engine warmed up.
After stripping re stripping and checking stack heights for the umteenth time, it turned out that the fluid in the reservoir was over filled despite it being bang on the indicator marks.
It could also be air or a bit of water in the system? the air / water is getting hot and expanding?
One last tip for all hydraulics brakes or clutch, to expel the very last of the air out; hold the system open over night if possible, I zip tye the levers to the handlebars, and hang a weight from the rear brake, the pin prick size bubbles will rise back through the system.
The end of the road is the start of the fun
A bad day on the bike is still better than a good day at the office
zimtim wrote:It looks like I am gouing to have to buy whole new brake system caliper, pads, lines and master cylinder before I can get going again.
Nah, you can't allow youself to be beaten by inanimate objects There will be one little thing that's causing this to happen one little link in the chain. I'd be starting with replacing the fluid if you haven't already. Is it coffee coloured? get rid.
When the brake is clean, serviced and cool, does the rear wheel spin freely (you may need to take the chain off to check)?
What happens when you apply it with the bike on a stand: does it release properly?
Bear in mind that what retracts the pistons (and allows the pads to release) is the master cylinder return spring: is the m/c piston sticking 'down' because the spring is faulty.
Is the disc itself warped or misaligned (if it's been repeatedly overheated through riding with a seized caliper then the answer is probably yes and servicing the caliper won't cure the problem that it has caused. You'll need a new disc)?
Is the rear wheel fitted and aligned correctly (spacers all correctly installed, spindle torqued to correct figure, chain running straight)?
And last but most important: where is your boot when you ride? It sounds like you could be applying the brake without realising it.
Don't waste any money until you have checked all of the above. In particular I would free off the brake and go for a ride without applying the rear brake at all and keeping your right toe on the footrest where it cannot possibly operate the brake. See what happens.
The (floating) calipers on my KTM have been known to seize; providing you deal with it straight away, a good kick or a blow with a rubber hammer will unstick them. In winter, I give them each a kick at the end of every ride to ensure they are fully released, and kick them again before setting out on the next ride. They get stripped and cleaned once a year, which should be enough.
Have been convinced that the problem was with the caliper but am now not so sure.
So I will be starting with a strip down and clean of the master cylinder, recleaning the caliper and all its parts will need to replace the brake pads and lastly flush out all old brake fluid and replace with new. Hopefully this will be the cheaper option at least I will be fully proficient at stripping down brake caliper and master cylinders at the end of this task.
