Front Brake Question - Lever Pull Is Mushy


7 replies to this topic
  • MR5627

Posted November 10, 2010 - 06:02 AM

#1

I bought a 2003 WR 450, and love everything but the front brake. The lever pull is mushy, and even after bleeding the brake twice with new fluid, I can still pull the lever back almost to the grip.

I adjusted the lever for full extension already. I want to be able to pull the lever without having it come back against my other fingers that are still on the throttle grip.

Do you think I might need to replace the internals on the master cylinder?

Thanks for your help.

  • Chas_M

Posted November 10, 2010 - 07:13 AM

#2

Did you back (reverse) bleed the brakes from the brake bleeder on the bottom to the top? That method works much better than traditional top to bottom bleeding since air bubbles rise to the top. A quick fix that sometimes works, with the forks turned so that the right handlebar at the highest level, is to gently pry the front brake pad into the caliper with large screwdriver. Then pump up the brake lever. Then repeat the process. This oftentimes forces air trapped up high into the master cylinder reservoir. Another trick is to bungy the brake lever in tight towards the handlebar and let sit overnight.

  • Krannie McKranface

Posted November 10, 2010 - 07:39 AM

#3

Did you back (reverse) bleed the brakes from the brake bleeder on the bottom to the top? That method works much better than traditional top to bottom bleeding since air bubbles rise to the top. A quick fix that sometimes works, with the forks turned so that the right handlebar at the highest level, is to gently pry the front brake pad into the caliper with large screwdriver. Then pump up the brake lever. Then repeat the process. This oftentimes forces air trapped up high into the master cylinder reservoir. Another trick is to bungy the brake lever in tight towards the handlebar and let sit overnight.


- adjust the lever to remove any slack
- zip tie the lever to the handlebar overnight

  • MR5627

Posted November 10, 2010 - 08:11 AM

#4

I bled from top to bottom with a vacuum bleeder. I will try your methods. Thanks much.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • MR5627

Posted November 10, 2010 - 08:11 AM

#5

Thanks. I will tie it back.

  • GCannon

Posted November 10, 2010 - 08:55 AM

#6

All the bleeding in the world will not fix the front brake if:

The front rotor is bent and pushing the pads apart with every revolution and that travel is made up by the master cylinder having to send more fluid to the caliper to make brake pad contact.

If the brake hose is old and badly beat up by hitting rocks where it curves under the fork leg. They can get pretty soft in this area.

If the caliper is not sliding on the pins from poor service.

  • MR5627

Posted November 10, 2010 - 01:56 PM

#7

Thanks. I will check all that also.

  • bmeador

Posted November 11, 2010 - 06:18 AM

#8

I have always had better luck with a Stainless Brake line than the cheap stock rubber ones. U might have a some wear on the master cylinder piston and it is bleeding pressure by the piston also.




 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.