Front Brake Issues

[axman2292]

Hello there,

I have a 02 yz426...LOVE IT! I am having one small issue I have not been able to figure out yet. When I pull my front brake it mashes all the way down & then I am able to roll my bike forward (the brake releases) If I pump it a couple of times it catches and stops the rim, but then goes right back to releasing.......So you ask...Did you bleed it?

Yes....not once but three different times...and still it is doing the same dang thing..HELP....?!?@?!$#?

Is it the master cylinder seal/fittings? Or maybe the line?...not to sure.No fluid leaks anywhere what so ever. Let me know if this has ever happened to you..and what you did.

Thanks, AXMAN:foul:

[CaptainKnobby]

You just need to keep bleeding it!....... You got to get all the air out and not one little bubble can be in there. I have bled the front brake before and took me an hour and went through a whole bottle of fluid before I got brakes.If there is no leaking around the seals and if you are getting brakes sometimes then everything is fine,just keep bleeding.

[Racer24]

bleed it at the master cylinder as well as the brake line and caliper

[martybec]

Put a zip tie around the lever overnight and then try bleeding it. I spent about 3 hours on mine and couldt get it, then I tried the zip tie and it worked for me. If my bike is going to set for a few days I will zip tie it.

[642MX]

The best way to bleed brakes on bikes is to use a vacuum bleeder. You can buy them pretty cheap at most auto parts stores. After using a VB, you won't ever think about manually bleeding them again.

[grayracer513]

https://www.thumpertalk.com/forum/showthread.php?p=4680701#post4680701

https://www.thumpertalk.com/forum/showthread.php?p=4681618#post4681618

If after the above procedures are done, you have a situation where air re-enters the system for no apparent reason, or one in which the lever moves slowly to the bar while moderate pressure is applied, the cylinder needs a rebuild.

[axman2292]

Thanks for all of the great responses..I finally will have time tomorrow to tackle this problem...then hopefully I will be riding on friday. Thanks Axman

[cowboyona426]

axman, something else you can try is this: go to a farm supply or vet supply store, and buy a large syringe for horses or cattle. Next go to the hardware store and buy some 1/4" tubing (I think that's the right size- just make sure it will fit over your bleeder valve on the caliper). Put one end of the tubing on the bleeder valve on the caliper, and the other end on the syringe. Open the bleeder, and pull the plunger out on the syringe. This will help suck the air out of the system, and although not as fast as a vacuum tool it gets the job done. I did this on my old 00 when I installed a CR style brake hose, and it took 20 minutes or so but it got the brakes working well. Good luck, hopefully it will work for you.

[Fastest1]

You can do just the reverse of what Cowboy said, fill the syringe with brake fluid and fill from the bleeder screw. Force the fluid up to the master cylinder all air will go with it. Take your caliper off while you bleed it, if it has stock hose routing.

[bg10459]

You can do just the reverse of what Cowboy said, fill the syringe with brake fluid and fill from the bleeder screw. Force the fluid up to the master cylinder all air will go with it. Take your caliper off while you bleed it, if it has stock hose routing.

Yep. ? Perfectly bled in less than a minute.

[axman2292]

I have tried everything that has been recommened and unfortunatly I have not had success. I am at a standstill now..and just about ready to pull my hair out...I guess I will have to rebuild it....I will post again when I have front brakes..thanks again to everyone that has posted.

Axman:crazy:

[axman2292]

Well...I figured out the problem with my front brake. After trying to bleed it every which way....reverse bleed, vacuum pump, standard bleed...I was not having any luck. Every time I would still have a lever that sunk all the way in and no front brake. So I called the dealer and ordered a Master Cylinder rebuild kit ($20) and spent about twenty minutes taking it a part and putting in the new kit. I bled it out with new fluid and it works like a charm......So if any of you have this problem that I did...don't even waste your time trying to bleed it 10 times like I did...just spend the 20 bucks and and save yourself some time and frustration.......Thanks for the replys,

Axman:applause:

by the way...I now prefer to bleed with a 30cc syringe....just take off the caliper..attach a hose to the syringe and then to the bleeder screw..hold the caliper in your hand with the syringe half full of fluid....have the master cap off and about 1/4 full of fluid..crack the screw and press fluid up through the screw....close it off..then pull fluid out of the master and repeat it over about 4 times....it works great