Toasted rear brake :(

[TAftonomos]

Went out for a ride after work yesterday.  I ended up cooking the rear brake.  I remember setting it up "loose" to ensure that there was enough travel and didn't result in a pump-up situation (which I've had before).  I'm not sure why this happened....maybe I was inadvertently applying the brake until it became hot...real hot....and no longer had freeplay in which to release?

Luckily, there was a pair of pliers nearby and I released the lock-nut and backed off the rod.  This released the brake....but now there is nothing there at all when I push on the pedal.  The rotor was smoking hot, so I may have warped it.  I can't detect any dragging now that the pads have released.  Going in to inspect now, but I figured someone out there has experienced this before.

Any thoughts?

[Speeddog]

Likely the 'stop' screw locknut was loose, and the screw backed out until the piston covered the bleed port.
IIRC, that was how the last victim here got caught.

Rotors can go cone shaped if gotten hot enough, they look flat until you loosen the mount bolts.
How far in toward the bolts is the paint burned off?

Throw a good (non-barbecued) set of pads in, complete flush and bleed, see if you've got anything.

[TAftonomos]

I ordered up a new set of pads.  Bled it until my hands bled.....still a bit spongy but maybe it's running out of travel as the pads are fairly worn   (they are about the same thickness as the backing plate)

Something I'm worried about is the pedal doesn't seem to be retracting far enough on it's own.  Even with the stop/brake switch adjusted in or out, it doesn't seem to want to retract far enough.....which is probably why this happened in the first place.

[Speeddog]

What bike is this on?

Return spring broken, bound up, missing?

[TAftonomos]

2007 s4rt

Now that you mention it....it's not there! 

[Speeddog]

Caliper wont run out of travel until a piston goes past the seal.
That won't happen even if you run the pads down to the metal.

SSS rear brakes are difficult to bleed, caliper must be removed and oriented with the bleed screw up.
Put a piece of scrap metal between the pads, 1/4" material works well.

[corey]

Caliper wont run out of travel until a piston goes past the seal.
That won't happen even if you run the pads down to the metal.

SSS rear brakes are difficult to bleed, caliper must be removed and oriented with the bleed screw up.
Put a piece of scrap metal between the pads, 1/4" material works well.

I've just given it up at this point. I've had that sucker clear upside down, bled it perfectly. 2 or 3 days later, sponge-tastic. I just don't use the damn thing, or mash it like the squishy potato it is.

[TAftonomos]

I bled mine upside down, seems rock solid with near-zero travel.  THanks again Speed!


Now.....the best I can tell there is no provision for or possibility of mounting up the OE return spring.  Maybe someone else knows or can show me....


I'm using S&P's rearsets btw.

[Speeddog]

I bled mine upside down, seems rock solid with near-zero travel.  THanks again Speed!

Now.....the best I can tell there is no provision for or possibility of mounting up the OE return spring.  Maybe someone else knows or can show me....

I'm using S&P's rearsets btw.

Very few aftermarket rearsets provide a return spring.

You could rig it up with a piece of innertube just to eliminate that from the suspect list for short term.

I've just given it up at this point. I've had that sucker clear upside down, bled it perfectly. 2 or 3 days later, sponge-tastic. I just don't use the damn thing, or mash it like the squishy potato it is.

I've seen a few bad master cylinders on the S*R bikes.
Most likely that's the issue.

[TAftonomos]

So far, so good.  Problem is if I adjust the brake switch/stop to activate when the rear brake is disengauged, the damn thing will pump up.  If I leave enough freeplay so that it won't pump up, half the time the brake light will be stuck on unless I left the lever up.  Thats a pain, and could get forgotten which isn't acceptable.

S&P says it shouldn't do this, yada yada.   Maybe I use the rear brake too much, but it sure settles the bike in nicely while rolling into a corner.

I'll have to rig up a return spring somehow.