No rear brakes on new used bike...

[shanet1975]

Hello....Merry Christmas eve. I just bought a used 99 kx 250 with non working rear brakes. If I losten the bleeder it spits so I think the cylinder is good. I can't get the caliper off for the life of me. Don't have a manual yet. Does anyone have a pdf manual for this or can tell me how to get it off. I bent 3 allen wrenches already trying to get the big allen bolt out. Not even sure if I have to do that though.
Thanks for your help...

 

[Tapkawiman]

It sounds like to me if it spits there is air in it and needs to be bleed out. But that still doesnt mean its good. Bleed the air out and then see how they work.

 

[shanet1975]

OK. Heres another stupid question. I losten the bleeder thing (not sure what it's called) and pump the breaks. Only a little fluid comes out and the pads don't move. I think it would be easier to take the caliper off. I'm going to try to get that thing off of there now....

 

[IndyMX]

Ok.. I think you first need to understand a couple of things..

1. Don't LOOSEN the bleeder then pump the BRAKE. That would only serve to suck air back into the system. Which does you no good.

2. You have to bleed the system, plus make sure that the fluid is good before there will be any action of the BRAKES.

So, fill the reservoir, then pump the pedal. After you pump it a few times, hold the pedal all the way down and then LOOSEN the bleeder. After a few seconds tighten the bleeder and only then do you release the pedal.

Repeat that process until you get a good flow of fluid coming out of the bleeder, with no air spitting out. It may take a while.

Then you should have the system bled.

If it still doesn't function after that process, you should then start to think about taking the caliper off of the bike for a rebuild.

 

[Tapkawiman]

If you are pushing the brake lever up and down while the bleeder screw is open you are sucking in air. Fill the brake res then pump the brakes, then while holding pressure down on the lever open the bleeder screw, do not let the brake lever go back up until you close the bleeder screw. Then repeat the process.

If you let the brake lever go up while the bleeder screw is open you are sucking air into the caliper which defeats the whole purpose. Repeatedly check the res to make sure you dont run out of fluid.

 

[IndyMX]

If you are pushing the brake lever up and down while the bleeder screw is open you are sucking in air. Fill the brake res then pump the brakes, then while holding pressure down on the lever open the bleeder screw, do not let the brake lever go back up until you close the bleeder screw. Then repeat the process.

If you let the brake lever go up while the bleeder screw is open you are sucking air into the caliper which defeats the whole purpose. Repeatedly check the res to make sure you dont run out of fluid.

Huh.. Exactly what I said, 14 minutes before you did.. :nener:

 

[shanet1975]

Got it. Thanks so much. I'll give that a shot. Do I fill the black cup rubber thing in the cup, or just underneath it?

 

[shanet1975]

So there is such thing as a caliper rebuild kit? I priced a new caliper and it was over 2 bills :(

 

[Rotorranch]

All the parts to rebuild a caliper are available from a dealer.

Try bleeding the brakes again.

Rotor

 

[shanet1975]

I'll try tomorrow. Hopefully it's that easy? What is included in a rebuild kit? Re they pricy?

 

[Rotorranch]

There will be piston seal, and a dust boot. That's all.

Check the online parts stores. Most have a parts microfiche to look up parts. They will show you what parts are needed, and the price.

www.bikebandit.com

www.motosport.com

www.babbittsonline.com

Rotor

 

[shanet1975]

Thank you again so much. I haven't owned a bike for about 10 years. And you are all so helpful.
Merry Christmas everyone and Happy Holidays for those of you who don't do Christmas!!!

 

[shanet1975]

OK. Got the caliper off. The piston is locked up...Any way to loosen that, or do I need a new piston?

 

[sixds]

did you even try bleeding it?

 

[shanet1975]

Yes. They wouldn't budge so I took them off after. The reason they wouldn't budge is the piston is locked and sealed in place. It won't move.......