warm/hot rear rotor

[wapam]

What is the general consensus on whether the rotor(s) should get warm/hot?

My rear gets very hot after just a little riding. If I stop, put the bike on the center stand and spin the rear wheel, it spins fine (about 1-1.5 turns). I can hear the pads against the rotor but the wheel spins fine.

When I got the bike the rear brake siezed pretty bad (smoking) so I rebuilt the MC, cleaned the spooge hole and that's where I am now. BTW, the brake works fine.

Thank you for any advice.

[olebiker]

If you get too much heat built up in your brakes they will eventually boil the brake fluid and seize your brakes on. They must still have some drag check them before you ride as well. Your wheel bearing ok?

[Ken Talbot]

Ride for a while at highway speed, pull over and stop using front brake only. The rear rotor should be cool or no more than just barely warm to touch. If it is at all hot, it is dragging and needs some attention. It could be the spooge hole plugging up again, it could be the pads not sliding easily in the caliper, it could be both.

BTW - the same sort of check will work for the front brakes too. Ride for a while at speed, pull over using engine braking and rear brake only, and the front rotors should be cool to the touch.

[wapam]

Thanks for the replies.

Should I hear the pads "dragging" on the rotor when I spin the wheel by hand? I hear a slight metallic scraping sound.

Thank you.

[skids]

That is normal.

Originally posted by wapam
Thanks for the replies.

Should I hear the pads "dragging" on the rotor when I spin the wheel by hand? I hear a slight metallic scraping sound.

Thank you.

[wapam]

If it's normal to have metallic pads dragging on a metal rotor (however slight), how could the rotor NOT get hot? Even a slight drag on a spinning rotor is going to build up heat quickly, use the brake a few times and the friction is maximized thus heating up even more.

Just trying to understand. I've read a lot of posts that say heating up of the rotor is normal and not to worry as long as the wheel is free and the brakes work.

Thanks again.

[trbig]

There's a difference between lightly touching the disc as you ride along, and slightly dragging. Though it's not enough to stop your wheel, the back brake sounds like it is dragging.. probably from a caliper not releasing enough after application. You can rub two sticks lightly together for hours without getting hot... add pressure and that's where the heat and energy starts rising.

If working and releasing properly, your brake discs won't get hot if done the way Ken Talbot posted.


Tod