Dragging rear brake :(

[Discofrank]

ok fellas i have a drama with my rear brake dragging
ie it is applied without me using the rear brake pedal

i have pulled the caliper off and removed the pads
the caliper does retract when the brake is applied the released as it should
and moves freely and i can push it back into the caliper with my hands

also re-lubed the caliper bolts that it slides on

the disc is not warped as far as i can tell
ie no brake lever pulsating when applying rear brake

i have looked at the caliper when on the bike and applied the rear brake
u can see the piston move and apply pressure to the pads
then it retracts
but for some reason the pads are not moving back with the piston?

i thought it may have been the hole where the locating pin goes as it was oval shaped but new pads are the same

will put them in tomoz to see if that helps but i doubt it will fix my drama




any ideas??

as this is causing rathign **** fuel econ and poor accel as you may imagine

 

[ozzieboy]

Just clarifying.....The pistons retract and the pads remain behind touching the disc?

If it was just the whole lot staying in, I would've said pressure in the lines and suggested very carefully remving the master cylinder cover to let it equalize (with a rag wrapped over it and plenty of water on hand to wash any spills off with).

I'm not sure about the just pads staying in problem...sorry man.

Hope you get to the bottom of it soon.:thumbup:

Cheers
Mike

 

[(none)]

When you put the bike on the centerstand, can you freely move the rear wheel? if so, there isn't a problem. Just because the pads are touching the rotor doesn't mean there is an issue. Did you replace the pads? If so, when you installed the pads, did you make sure the sliders the pads slide on were cleaned?

 

[Boneman]

When you put the bike on the centerstand, can you freely move the rear wheel? if so, there isn't a problem. Just because the pads are touching the rotor doesn't mean there is an issue. Did you replace the pads? If so, when you installed the pads, did you make sure the sliders the pads slide on were cleaned?

+1

I remember after installing my EBC brake pads that the rear would "rub' a little when turing the rear tire by hand. Much like I do when I change my car brakes, I took the bike for a ride and did a few heavy braking stops to help 'seat' the pads a little better. After that it stopped. It' s not uncommon for the pads to rest on the rotor.

Also might want to try carefully pushing the pistons back into the housing a bit on the rear caliper. A small block of wood and some firm preasure works. I had to do this when installing new pads as they were thicker and I needed more 'room' in order to get teh pads in and around the rotor.

 

[Discofrank]

When you put the bike on the centerstand, can you freely move the rear wheel? if so, there isn't a problem. Just because the pads are touching the rotor doesn't mean there is an issue. Did you replace the pads? If so, when you installed the pads, did you make sure the sliders the pads slide on were cleaned?

sorry should have stated that NO i cannot freely move the rear wheel on the centre stand
same as if i go for a 10 min ride without using the rear brake it gets too hot to touch!

the brake is dragging

i know the pads touching the rotor is not an issue as they should move back just enough to allow the disc to spin



i have new pads here but i highly doubt they will fix the problem

there is only 1 pin that they slide on and a metal slid

might grease it up with hi temp bearing grease

 

[Discofrank]

UPDATE****



ok seems that new pads did not fix the issue

i think i may have a damaged spring the one that sits inside the caliper...


yay goign to be a 3 week wait ex japan i think

 

[Norbert]

UPDATE****



ok seems that new pads did not fix the issue

i think i may have a damaged spring the one that sits inside the caliper...


yay goign to be a 3 week wait ex japan i think

Spring in caliper?

 

[TownsendsFJR1300]

I think he's referring to the anti-rattle spring (SS, somewhat flat, rectangular)...

Scott

DiscoFrank- Make sure the new pads are not binding or hanging up in the main brake caliber. I suspect the caliber piston may have crap in there and require disassembly and cleaning. After cleaning/flushing use brake specific grease for the seals if you end up going this route,,,,

 

[flashgordon]

just a long shot but have you checked the wheel alinement as this would throw the disc off line? :Flash:

 

[Discofrank]

Spring in caliper?

I think he's referring to the anti-rattle spring (SS, somewhat flat, rectangular)...

Scott

DiscoFrank- Make sure the new pads are not binding or hanging up in the main brake caliber. I suspect the calliper piston may have crap in there and require disassembly and cleaning. After cleaning/flushing use brake specific grease for the seals if you end up going this route,,,,

nope not the anty rattle spring they are on the pads

there is a U shaped spring which sits inside the calliper and ontop of the brake pads if u have a look at the service manual it is in there

just a long shot but have you checked the wheel alinement as this would throw the disc off line? :Flash:

thats what i thought but have undone the chain adjusters and pushed them forward flush and only rotating the wheel by hand


this only happened after i installed new sprockets i wonder if i damaged he rear disc, it does not seem likely as the disc sits inside the rear wheel

 

[TownsendsFJR1300]

I wasn't referring to the brake pad shims, but the "brake pad spring" (part #7). Its the only thing considered/mentioned as a spring in the rear brake in the Yamaha manual... I was trying to clarify for OMG_WTF.

As stated earlier the caliber piston will probably have to be removed and cleaned. It does not take much to hang up....

I don't know what year bike you have so I don't know if the below may apply.


From page 4-34 service manual on-line:

Recommended brake component

replacement schedule
Brake pads If necessary
Piston seals Every two years
Brake hoses Every four years
Brake fluid
Every two years and
whenever the brake is
disassembled.

As a side note: My 07 FZ6 front brakes and 04 FJR front brakes began dragging (the rear brakes been fine). The FJR got cleaned (didn't look dirty) and new seals. The FZ6, I took apart and cleaned the pistons, calibers, seals. I also used brake specific grease for the seals/pistons... No more dragging on either...

Scott

 

[Norbert]

I always imagined springs to look more like a Slinky.
I learned something today.

 

[Discofrank]

I wasn't referring to the brake pad shims, but the "brake pad spring" (part #7). Its the only thing considered/mentioned as a spring in the rear brake in the Yamaha manual... I was trying to clarify for OMG_WTF.

ahh got ya

As stated earlier the caliber piston will probably have to be removed and cleaned. It does not take much to hang up....


As a side note: My 07 FZ6 front brakes and 04 FJR front brakes began dragging (the rear brakes been fine). The FJR got cleaned (didn't look dirty) and new seals. The FZ6, I took apart and cleaned the pistons, calibers, seals. I also used brake specific grease for the seals/pistons... No more dragging on either...

Scott

aorry it is on 06 bike but all teh rear brakes are the same

even if i can see the actual piston moving back?
ya brake specific grease is known as rubber grease here in aus

 

[TownsendsFJR1300]

This is what I use:

http://www.permatex.com/documents/tds/Automotive/24110.pdf

It is designed for brake seals, pistons etc. I don't know if the grease your referring to is compatable with the rubber seals, fluid etc. As stated in earlier posts, the pads just have to retract just a little to prevent dragging. The seals help pull the pistons back just a very sllight bit. If the brake pad pin that go thru the pads are scored up, they should be cleaned up replaced... They also need greasing.

Yamaha recommends replacing the seals every 2 years.

My 2004 FJR fronts were dragging bad. With the ft raised, spin the wheel by hand, it stopped immediatly.. Cleaning up the pistons/caliber, installing new seals and then assembling with the included brake grease fixed the problem. It now free spins approx 3/4 turn.

For my 07 FZ6 front brakes, they were just starting to drag, I R&R'ed both front calibers, greased all the seals and pistons, its fine now. The inside looked clean when pulled apart. BTW, I could push the pistons back in by hand on all the calibers prior to disassembly HOWEVER the brakes still dragged..

You can probably get by with cleaning all parts, re-greasing with brake specific grease, refill with new fluid. That is as long as there's no leaks... Its not that hard to do...

The seal kit for the rear shouldn't be too expensive as its a single piston. The front kits, to do 8 pistons (4 on each caliber) was about $130.

Hope this helps...

Scott

 

[Discofrank]

well issue still not fixed

pulled the caliper out and the piston

re lubed with rubber grease

new pads installed with a newer spring
re bled the brakes with new dot 4 fluid

still the same ****ign thing

i have no clue at all

going to take it to a mech i think

 

[TownsendsFJR1300]

Did you find the problem?

 

[n0other]

I think my rear brake is dragging as well, did you ever managed to fix this?

When spinning the wheel by hand, giving a relatively good spin it stops after doing 1/4 to 1/2 rotation, also, I can hear the brake pad brushing the disc. When I apply the foot break, I don't see any change in brake pad touching the disc, that is, it doesn't move any.

Is that considered normal?

 

[Nelly]

ok fellas i have a drama with my rear brake dragging
ie it is applied without me using the rear brake pedal

i have pulled the caliper off and removed the pads
the caliper does retract when the brake is applied the released as it should
and moves freely and i can push it back into the caliper with my hands

also re-lubed the caliper bolts that it slides on

the disc is not warped as far as i can tell
ie no brake lever pulsating when applying rear brake

i have looked at the caliper when on the bike and applied the rear brake
u can see the piston move and apply pressure to the pads
then it retracts
but for some reason the pads are not moving back with the piston?

i thought it may have been the hole where the locating pin goes as it was oval shaped but new pads are the same

will put them in tomoz to see if that helps but i doubt it will fix my drama




any ideas??

as this is causing rathign **** fuel econ and poor accel as you may imagine

Hi mate, you really need to rule out warped disc. I went all round the houses with the same issue. Are the pads wearing unevenly? The only way to absolutely rule this out is by removing the rota. 30 min job and checking with callipers.
http://www.600riders.com/forum/garage-mechanical-help/44793-resolved-abnormal-wear-rear-brake-hanger-what-have-i-done-help.html
It was caused by the pad pin not allowing the disc to float due to constant wet riding and not enough maintenance.
Good luck
Neil

 

[adamyorkie]

Hi

How did you sort this I have exactly the same problem, the caliper moves freely, taken apart all cleaned but after a short ride with just gentle back brake usage it is mad hot to touch compared to the front that are cold.

I have the abs version which kicks in fine if I smack on at the back.

 

[Beerdrinker]

I had something like this, went to Yamaha dealer and they repaired,
it appears I had a crockett and rusty pin... it won't let one of the pads to turn back after releasing the brakes so it forces only one brake pad dragging.
they clean it, new brake pads, new pin and it is as new! this was one week ago. hope it helps