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Discussion Starter · #1 ·
Hey guys,

Having a bit of an issue as of late with my rear brake. It always felt a little off to me and I've adjusted it as much as I can, but now it doesn't seem to be totally disengaging when the lever is released i.e. the pads are still touching the rotor slightly. After my ride yesterday the rear rotor was pretty warm almost hot and the front was nice and cool'ish in comparison.

What advice can you guys suggest to solve the issue? bleed the rear brake and replace with fresh fluid? Would this solve the issue? or do I need to remove the rear caliper and check things out a little deeper. On visual inspection there is plenty of life left in the pads, for now anyway!

Thanks,

Rich
 

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Make sure your return spring is intact....

Both Psyco and myself both found ourselves with broken return springs while up in the WNC mountains this May....
 

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Discussion Starter · #3 ·
Sorry, not much experience with brake work..... return spring... same as leaf spring (term from repair manual) in the caliper?
 

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Simple things first...check to make sure your chain adjustment blocks are even from side-to-side to make sure your wheel is not cocked sideways a bit.
Other than that, most likely you're not getting full return of the lever which allows the last bit of line pressure to build up instead of release.
 

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I've worked on a ton of brakes, and never have seen a "return spring". Figure 8 on page 27 is showing a seal. At least that’s what I'm seeing.
Old fluid will crystallize and get behind the seals applying too much pressure on the piston which will not allow them to retract properly. Could be dirt too. You need to pull the caliper, take it apart and clean it. You can usually use the same seals if they are not torn at all. Use your fingernail while stretching the seal. It cleans them right up. If you have hardened fluid in the grooves, use a Demmel with the small wire wheel, along with some WD-40 and that will clean the groove right out. Put a little brake fluid on the seal, and put them back in the groove. Oh, to get the pistons out, take the two halves apart; wrap a towel around it, leaving the bleeder nipple in place, and use air with one of the rubber nipples jammed into the hole where the line would go in. The towel is to keep your fingers on your hand when the piston releases and comes flying out at light speed. If you take the two halves apart, watch for the small o-rings, and where they go. Find out the torque specks, re-torque the two halves using blue locktight, and re-torque the calipers back on doing the same. Always use lock tight on the caliper bolts, and torque them correctly. Or send it to me and I’ll have it going back to you the same day I receive it.
 

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A friend used a small spring between the pads (the pin running through it) and it worked great :thumbup:

As for cleaning, these calipers have a black shiny, sort of anti-stick coating, and they are easy to clean, I used just a toothbrush.

Just take out the caliper, press the brake a bit, clean it, grease it (using the special brembo grease) and put it back.

You may want to also grease the slide, not sure what kind of grease it needs

maybe something like this: http://www.amazon.com/CRC-SL3302-Sy...=2025&creative=165953&creativeASIN=B000M8O05Q
 

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I had a similar problem, after a fall in the dirt the rear pads wouldn't release anymore when releasing the brake lever, after a bit of riding they would slowly move out though.
I cleaned the caliper and renewed the oil, some air got into it. Afterwards, the problem was gone.
 

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Discussion Starter · #9 · (Edited)
I've worked on a ton of brakes, and never have seen a "return spring". Figure 8 on page 27 is showing a seal.
Thanks for the advice ... going to try the simpler routes first.. but if I end up going this route I'm sure you'll be getting a pm from me with a question or 6

This is the spring HOLLYWOOD33 is talking about on page 27...


HOLLYWOOD33...Spring appears to be fine.... haven't had a chance to get a really good look at it.. could you tell with a visual inspection or did you have to pull it off?.... will get a chance tonight... and if all is OK... I will probably pull the caliper off this weekend if we don't end up going camping.

Thanks for all the advice guys.... keep it coming if you think of anything else.. and I'll give an update when I get an hour to look at it tonight
 

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The brake pads are going to be in constant contact with the rotor. Sure, you can put a spring between the pads (Why anyone would do this, I don't know), but there is no need to. As soon as you release the rear brake pedal, the rotor will bump return the pistons. If you suspect that the pistons are not returning, clean the rear caliper (and master cylinder). That little spring on the pedal has been broken on my bike for a while now, and I haven't had any issues with the rear brake dragging. My GSX-R750 track bike doesn't have any "return spring" either. The spring is there to ensure that the brake light switch doesn't stay "on".
 

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That spring is so soft that i doubt it could cause the problem.

There is something like a piston just behind the brake lever(page 27 part 14 in the manual), which like to get stucked, just spray some WD40 on it, might do the job.
 

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Had a problem with a broken spring on mine also. I put a new one on and connected a stronger one one also, safety wired both up, as mine is a race bike only.
 
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