Triumphrat

ohiorider

I had just returned from a short, 15 mile ride, and it was time once again to lube the chain. I brushed up against the rear brake rotor, and noticed it was extremely hot. Checked the front rotor, barely warm. I don't ride the rear brake, and typically use it mostly in very slow traffic, so I don't think operator error is causing the heat problem.

Have any of you experienced overheating brakes? I'm thinking the cause may be sticky caliper pistons that are causing the pads to stay in too close contact with the rotor. Or perhaps the pins that support the pads need cleaned and lubed with some high temp grease. I'll check these things first.

Any other suggestions about what to look for? I'm about ready to change rear pads, and don't want to total them because I've overlooked some simple fix.

Bob

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2003 T100 (790cc) Lucifer Org and Silv: 122/42 jets, TORs, 17T, UNI filter, no AI, Polaris bellmouth, Metzeler ME880 tires, Progressive 440 shocks (105/150 springs),11-1126 fork springs, gaiters, MotoTwin low bars, 6024 lamp, htd grips, 12v outlet.

Normandy

Try getting your back wheel off the ground and turn the wheel by hand to feel the drag. There will be some and the disc will get hot but too hot will glaze the pads and can warp the disc. If you are doing the pads anyway, this is the opportunity to correct any problem that may exist unless it's in the master cyl.

thrux351

Bonnies are known for having the rear pads hanging up on their pins when they get dirty or corroded-easy fix-clean up the pins and lube. Also make sure the reservoir is not overfilled, as this too can cause dragging brakes once the fluid heats up.

lindsayt

My bike's always been that way. I've had it checked out by a couple people, checked it out a couple times myself, nothing's wrong. no runout, no pad dragging, no nothing.

Touch your car's discs right after you stop the car, you'll find they're incredibly hot. My scooter's front disc is ungodly hot. The front disc on the Bonnie isn't hot only because it's in front of the bike's slipstream, which means it gets massive air over it all the time. The rear disc doesn't, so it has to radiate heat through convection.

Remember that modern disc systems never actually lift the pads off the rotors - they're constantly rubbing, just with no force down on them except when you hit the brakes. This is what allows modern discs to have such incredible power, but it also means there's *always* some friction between the pads and the rotor. This generates heat, and of course when you apply your brake, it generates tremendous amounts of heat. Add to that the fact that our bikes have stainless steel rotors, which do not conduct heat very well at all compared to other metals, and you can see that things can get very hot.

I've decided not to worry about it - I've never noticed any fade on the rear brake, and I guess if I were ever cold and stuck next to a broken bike, the rear disc could keep my hands warm for hours!

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38% rocker, 30% mod.

Baltobonneville

I find it interesting that the pads do not lift off the rotor, they just sit there. I've noticed that the rear rubs a bit, and my pads are about half gone at 7500 miles even though I use the rear brake lightly and don't ride it.

I've also decided not to worry about it.

Someone mentioned in another thread that a misaligned rear wheel (from chain adjustment) can affect the brake, which makes sense to me. One of the things that I check for chain adjustment is any irregularity in the "rubbing" of the rear disk.

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Marty
2005 Bonneville Blue 790cc, AI removed, Staintunes, Unifilter, no snorkel, 120/40/Thrux needle/1 shim/3 turns, fly screen, tacho, D9 gauge panel, center stand, Ikon 7610s, Hagon fork springs, gaiters, Pirelli Sport Demons, 3 seats.

CAPTDON

Never touched mine after a ride but i am sure its hot. On the jack there is a slight "sound". The brake got 6000 mi on it & close to replacement. As said your car does the same thing. Unless its warping - not to worry. They never actually do not touch. If there is a real drag on it - then there is a problem.

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CAPT D

Normandy

Not really, the caliper and disc move with the wheel so would be uneffected by misalignment.

BLKTHRUX

The caliper doesn't move.

Geoff

i'm glad my caliper does not move with my wheel...that would be bad
G

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I never wanted to lead, and I never wanted to follow.
I just wanted to ride

Normandy

Move with the wheel "side to side", you guys pulling my chain ?