Rear brake rubbing/ contact

[jcombs]

http://www.youtube.com/watch?v=fQnzqnVWgjc
Hopefully my video makes it on here. How much contact is acceptable/expected when rear brake not being applied?.

 

[greg]

mine used to be like that, it should touch, but be a little freer

check your wheel spacers are clean and lubed up, that there's no crud on the brake calliper holder, clean and lubed sliding calliper bolts, and that the rear wheel nut is correctly torqued. also check the brake pedal has a little free play before the brake activates.

 

[McLovin]

mine rubs a little as well

 

[TownsendsFJR1300]

Looks pretty normal to me.. You have to remember you have chain drag as well..

Some brake cleaner and compressed air (not excessive, just enough for the dust to come out) should rid any dust/crud build up as well.. As noted above, a little brake grease on the slider pin helps..

You can also gently put a screw driver between the disc and the pad and push the piston back slightly just to make sure it isn't frozen...

Its pretty rare the rear piston drags bad, the fronts, that's another story.. Yamaha does recommend replacing the brake seals every 2 years. A new brake seal /dust seal would certainly allow it to release as if new...

 

[QwickFliCk]

i thought that was normal... mine does that in the front brakes too!:spank:

 

[greg]

my front dragged after i changed pads, turned out there was crud at the end of the slider pins, pushing the calliper into the disc

the rear should spin at least 1 revolution fairly easily too, check everything is clean, greased, and correctly aligned

 

[TownsendsFJR1300]

When I can't get more than 3/4 a rotation on my front tire (free spin by hand), the calibers get pulled apart, cleaned, the pistons re-greased with brake specific grease. I'll get 3 full turns after that.. Next time, I'll replace the seals as well..


[ame=http://www.amazon.com/gp/product/B0018PSASU]Amazon.com: Permatex 24125 Ceramic Extreme Brake Lubricant - 8 oz.: Automotive[/ame]

 

[FinalImpact]

Air trapped in the system will cause drag when warm as the air expands. So you could check it all cold and find its OK and then check it later during a ride and find drag. Bleed the system if this is the case.

Its a good idea to confirm the master cylinder push rod has free play. Hint there should be a gap on the front lever and actual freeplay at the clevis on the rear. If there is no freeplay it will cause brake drag as the caliper can be hydraulically holding the pistons out. Aside from added wear this could cause brake failure as a the brake system relies on the master cylinder to supply fluid from the reservoir and if the brake is partially on, it blocks the feed port so no fresh fluid can enter the system.

 

[jcombs]

Its a good idea to confirm the master cylinder push rod has free play. Hint there should be a gap on the front lever and actual freeplay at the clevis on the rear.

I don't know what a master cylinder push rod or a clevis is : (

 

[deeptekkie]

Mine has always dragged a bit. The pads look fine, the bike runs like a scalded dog, I just don't worry about it. (My front wheel will spin easily by hand) Safe riding!

 

[shamrocker]

Mine has always dragged a little. I've bled the rear brake several times, as well as changed pads, checked alignment, etc. The brake works fine, though.

I've noticed that it's not easy to find seals for that brake, does anyone have suggestions as the best place to find them so that I could rebuild the caliper?