2000 yz426f Bleeding Front Brake

3 replies to this topic
  • 5point9

Posted January 29, 2014 - 04:59 PM


Guys, I'm struggling to get my front brake to build any good pressure. As soon as I did the usual pull level, loosen bleed valve quickly, tighten valve quickly, release lever technique all of my pressure was gone. I finally got some pressure to build after playing with it and using a huge bottle of fluid. Argh.


I've zip tied the level over night and that helped some, at least for a while it seemed. I tried bleeding at the master cylinder bolt, and at the caliper bolt. Same or less results. Why are my brakes so spongy and weak? The pads are ok, no fluid is leaking. 


Thoughts? I've heard this year bike is hard to bleed. Is there any benefit to trying a brake bleeder/vacuum thingy?



  • nuity5

Posted January 29, 2014 - 06:04 PM


If the brake hose routing is similar to the layer yz's one area I've had trouble with is trapped air next to the caliper. The hose goes down the fork leg, back up then turns back down to the caliper and creates a location to trap air. Try pulling the caliper and let it hang to the floor so the brake hose is straight. Then air has a clear path to go which way it wants to go - up. I usually start by pushing fluid from the caliper back into the master with a syringe. Tap the entire length of the line to help bubbles to move. Then pump the lever to get the caliper full. Put a spacer in between the pads - I don't think it could push the pistons out with pads in but I use the spacer anyway. Then pump the master up and crack the bleeder on the caliper. I've had to go back and forth with this a few times but it has worked well for me. Clay

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  • cowboyona426

Posted January 29, 2014 - 06:08 PM


Buy a Mityvac and do it the easy way!

  • 5point9

Posted January 29, 2014 - 06:09 PM


Ok I'll try that next! Thanks for the response.

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