The Yamaha Road Star Warrior Forum

I just removed my rear tire to change it.  After I put my tire back on I noticed that the brake was rubbing against the rotor.  So I took the tire back off and and looked at the brake caliper.  The 'piston' was out so i I used some pliers to to put them back into place (flush).  After i put my tire back on and tested the rear brake it was stuck out again. Did the whole thing again of removing tire and pressing the piston back in. 

I didnt remove any cables to get the brake off the rotor.  There was two bolts on the brake, i removed one and just loosened the other on enough to remove it (there was the cable bolt in the way, didnt want to remove it).

So what is the next steps I should do. Is something locked on my brake? I thought replacing tire was supposed to be easy :P

thanks for any advice.

Is the rear break stuck on?  Can you still spin the tire?  The pads may touch the rotor a little, but it shouldn't seize the wheel in place.  Is this happening? Can you also post a picture?

 I will after i get home from work tomorrow, tire changing got me tired.

what happens is when i press the brake, it would go all the way down (feels good), then the next time it would go down half way, then the next time get a little tighter, t the brake pedal moves down about 1 inch and is tight.   I turn the wheel and it i can hear it grind.  took it down the street and back...the rotor is kinda hot.

Whey You Say Your "Brake Is Rubbing" I Assume You Mean That Your Brake Pads? Like There Not Releasing Pressure Like They Sould?

If They Are Not Dragging To The Point Of Causing Constant Resistance I Say Run It Up To Full Operating Temp (5-10 Mile Stop And Go) Then Check It Again...

REMEMBER, ANY TIME YOU WORK ON THE BIKE, ITS A GOOD IDEA TO WEAR A HELMET.... Learned That Lesson The Hard Way Once :)

 here is a pic.  When it is flush it does not rub.  Like i said..the first time works then when I press the brake..it takes like 3 times to get it to lock.  I dont think the piston is releasing back to flush.

 You do understand that there are no return springs on disc brakes, correct??

repsol61:

 You do understand that there are no return springs on disc brakes, correct??

so does that mean I have a bad piston?  It does not return to the correct place.  Do you think i need to bleed the brake even though I didnt even remove any cables?  Im just looking to ride without it scraping the whole way.

thanks for any advice.

Well first off and my $0.02 - If You dont understand how the brakes work - take it to a shop - It is not worth the trouble that can be caused by a brake failure.

Now being disk type the only thing I know that will pull the pads off the rotor is the dust boot. That is why pads have a tendency to drag slightly.  When you pull the lever, force is being transmitted through the fluid pushing out the piston.  When you release the lever the force is removed allowing for the dust boot to pull the piston back in.

Chim in guys if I'm wrong 

hippo:

 here is a pic.  When it is flush it does not rub.  Like i said..the first time works then when I press the brake..it takes like 3 times to get it to lock.  I dont think the piston is releasing back to flush.

 

my wheels are rc  wheels with a fixed rotor as opposed to a floating rotor but i hear  my pads dragging all the time, probably has always been this way and just never noticed it till now

 as was said earlier.

There is no return system that pulls that pads completely away from the disc.  I can hear my brake pads rub a little when i first pull out from a stop and if I were to pull over after a ride of any distance and feel the rotor; it's gonna be warm.  Not too hot to touch unless you were just on the brakes hard.  Just warm.  

Consider the fact that when you manually push the piston back flush, it then has to move a large distance when you first hit the brakes.  Then it has to move less the next time.  Disc brake pads generally sit very very very close to or actualy rub  the rotor. The caliper is not designed in such a way that the piston will return to a flush position after use.  That's not how it works.

Spin the wheel by hand.  If there doesn't seem to be brake related resistance then you're fine.

One odd possiblity that I had happen in a car was the brake line itself had deterioted internally.  Under braking pressure fluid would be forced to the caliper, but the hose internally collapsed and would not let it return, essentially creating a anti-drainback valve.  The conditions of what you are experiencing seem very similar and it took some time to diagnose on the car.

bgriffin509:

One odd possiblity that I had happen in a car was the brake line itself had deterioted internally.  Under braking pressure fluid would be forced to the caliper, but the hose internally collapsed and would not let it return, essentially creating a anti-drainback valve.  The conditions of what you are experiencing seem very similar and it took some time to diagnose on the car.

 

 

This is VERY EASY TO TEST FOR...

Raise Rear Of Bike, Spin The Rear Wheel And Hit The Brakes, Wait for it to stop, spin it again, see if it is DRAGGING or just RIDING on the rotor...

IF IT IS DRAGGING DO THIS TO TEST FOR COLLAPSED HOSE...

Put a pri bar between the rotor and pad, pry back GENTLY Untill The Pad Does Not Touch.. Does the Piston Go Back? How Fast? How Much Resistance?

Pump The Brakes back up, and spin agian, stop it.... Dont Pri This Time, But Crack The Bleader on the Caliper... Does The Piston Go In When You Do This By Itself? If It Does Then You More Than Likely Have A Blockage Of Some Type In The System..... You Can Allways Try Power Bleeding The Brakes, Or Manually Bleeding them a few times, (getting lots of fluid out and adding as needed to not let your master cylinder go dry) and see if that helps before trying to replace lines or anyting... may just have some trash in there that needed to come out, or contaminated fluid...

If that does not help, then start looking at your lines....

HAVE YOU GOTTEN THEM UP TO OPPERATING TEMPATURE YET??? I WOULD DO THAT BEFORE I DID ANYTING ELESE...

 Thanks, nate....very descriptive

hippo:

I didnt remove any cables to get the brake off the rotor.  There was two bolts on the brake, i removed one and just loosened the other on enough to remove it (there was the cable bolt in the way, didnt want to remove it).

So what is the next steps I should do. Is something locked on my brake? I thought replacing tire was supposed to be easy :P

thanks for any advice.

You have Supreme Legends Forward Controls that come with a SS brake line from either Galfer or Spiegler, i suspect, and will not fail in that fashion because of the construction.

For maintenance accessibility and troublshooting i would suggest you tweak very slightly & carefully the rear brake hose at the banjo bolt connection so that you can remove the forward facing caliper pin or if req'd reorientate the fitting very slightly. You don't need to bleed the brakes to do the aforementioned!

With the caliper body set aside inspect very carefully that the inboard/outboard pads and hardware are positioned properly in the caliper bracket opening.

Read this referenced post for my explanation of normal pad rubbing which also applies to the rear system except that the rotor is rigid and the caliper floats on the 2-pins.
Front brake constantly rubbing rotor?!?!? http://rswarrior.com/forums/p/109609/905652.aspx#905652

Additionally,IMO, if your rear wheel isn't adjusted squarely the pads and caliper aren't in perfect alignment and they will need to be reseated or fingerprinted from riding. I always observe the in/out pad markings left from the caliper piston and finger so that they go back in the same way.