BRAKE BLEEDING HELP PLEASE

[billinom8s]

right, need some info please.

been trying to get the front brakes to work on the old R1 since its rebuild, only problem is that its not working. no matter how much i bleed them they dont seem to get any better. the pads are fine and the discs are true and have plenty of wear in them. no air is coming out when bled either.

there seems to be good pressure while the bike is stationary but when its moved, the pressure seems to fade away rapidly, there are no leaks and all the nuts and nipples are done up tight.

any ideas ?

[CvPiper]

The only reason I can think of that the refuse to work properly on the move is that a disc is buckled/bowed, it then pushes the pads back in the caliper when moving, and thus won't work properly when you go to brake again, at standstill this wouldn't cause a problem.

[deej]

have you bled the master cylinder ?
it was the only way to get my brembo to work

[Maver-Nick]

Your brakes are bleeding...

Put a plaster on them...

[Smiler]

Had a nightmare with a KTM recently - in the end we used a syringe and forced clean fluid up the the reservoir from the bottom. Small amount of air released, but seemed to make quite a difference. I would suggest tho, that maybe in your case, it may not be quite so simple...

sorry, not an expert - just my 2p!

[billinom8s]

turns out it was one of the discs. sold as straight,hmmmmmm about as straight as a room full of funkys and bambams !

still, i had a spare and now its all working fine !!!!!!!!!!!!

thanks for the help and advice

[Mervin]

Had a nightmare with a KTM recently - in the end we used a syringe and forced clean fluid up the the reservoir from the bottom. Small amount of air released, but seemed to make quite a difference. I would suggest tho, that maybe in your case, it may not be quite so simple...

sorry, not an expert - just my 2p!

works every time for me that one, i don't bother trying to bleed from the top down anymore just blow it back up save hours, pumping the lever to no avail
Merv

[CvPiper]

[baz-R]

just a few tips for all you bleaders out there and its suprising how some of us miss the simple things
so heres a few of the thing i have come across in the past.

if your having a bit of trouble try and make sure there are no high loops of pipe (like a loopover setup from one caliper to the other) you can take off the caliper and place a packer to stop the pistons moving out and hang it down giving it a stright run.

another one is to pump the pistons out as far as you can leave for a minute or two and push them back in pushing the bubble back to the master cyl.

when a master cyl is open (fully off position) thair is a open line to allow the fluid in the system to be at air pressure and alow for expansion/contraction.
so if you fill the res and open the nipple the fluid will run down hill and find its way out just by waiting for the fluid to start to drip out bleeding by gravity. all while you make a brew

another one is little bubbles can get traped and serface tension prevent them from moving to help get rid of thease apply pressure to the master over night making the bubble smaller and helping it to work its way to rise to the top of the system removing the pressure in the morning should let it out the master cyl. it works you know i have used this meny times