Help with Brakes Please!

4 replies to this topic
  • 5point9

Posted October 06, 2013 - 01:22 PM


2000 yz426. The front brake was ok, but not real strong. So I removed the caliper, inspected the pads (which ended up being ok), cleaned everything and put it back together. At that point, I thought maybe I should just bleed them. As soon as I did my usual bleed job (squeeze, open valve, close valve, release lever) I immediately lost a lot of pressure. I had nothing for quite a while, but eventually got some braking, but very little.


I cant seem to get the pressure back up, even to where it used to be. I am almost through one bottle. I seem to have gotten most of the air bubbles out of the master cylinder. I tried bleeding through the banjo bolts as well, nothing. It just seems like the fluid does not "burst" out when pressure is applied. Just dribbles. 


Again, the brakes were ok before, not great. Now I've got nothing just from cracking the valve open once!



  • ekulb14

Posted October 06, 2013 - 06:33 PM


try reveerse bleeding. Get a syringe and push the fliud up from the valve. sounds like you got air in there somewhere.  

Edited by ekulb14, October 06, 2013 - 06:34 PM.

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  • 5point9

Posted October 07, 2013 - 02:07 AM


ok will do.


if it's a master cylinder problem, i would just find it hard to believe that it convienently started when I went to bleed the system! argh!

  • stroker101

Posted October 07, 2013 - 10:25 AM


u can try removing the brake caliper, remove the master cylinder cap,...then pry the pads apart, forcing the piston back into the caliper. this may force any trapped air back up and through the M.C. u may have to pump the system up a few times and repeat. don't use the banjo bolt as a bleed off point.

once u get that firmer feeling at the lever, do a final bleed off at the bleeder valve on the caliper. use very small openings there, just enuff to allow fluid to pass and without the lever to blow through it's action.


(be sure to place something in between the pads so not to force the piston out of the caliper when applying the brake)

Edited by stroker101, October 07, 2013 - 10:31 AM.

  • Rkumle09yz450f

Posted October 11, 2013 - 10:09 AM


I had the same problem I found that if I take the lever off and put a 7 mm deep well socket on the pin and push in and out slow and hold it for a few seconds works takes like 10-15 from line being empty but the cause was the lever did not allow the pin to full release inside the master so it would not let the air come back up threw and after I did that I could crack the bleeder and keep adding break fluid as it would go down the line an fill up the caliper and out the bleeder then bleed it like normal and worked fine,

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