Brake Disk Rotor Warp

**Motor** · #1 21 Oct 2003

Hi all, my bike (Honda CB1000 95') has developed an unusual problem, the brake disk rotor has warped to the point that it's touching the fork leg. I called the dealer and they say the new rotor costs almost $400 USD. I wasn't even abusing the brake when it happened, does anyone know what causes this? Can this be fixed? Could it happen again, to the new rotor?
Any advice would be greatly appreciated.
Motor.

[This message has been edited by Motor (edited 21 October 2003).]

**davidmc** · #2 25 Oct 2003

Warping is usually caused by excess heat building up on the rotors. The rotor expands from the heat and if it is rigidly attached to the carrier, it has no where to move and will warp.

I went through 2 sets of rotors in less than 30k miles on my BMW K75. The brake rotors on my bike were notorious for warping. The best solution is to get a set of semi-floating rotors which allow the rotor to expand and contract. I installed these on my bike and haven't had a problem since. A good aftermaket set will probably be less $$$ than stock as well.

Another possiblilty is that the rotor was damaged if you had a tire mounted recently. If the mechanic was careless, he could have bent the rotor while the wheel was on the ground.

Hope this helps...

**Motor** · #3 27 Oct 2003

You are right Davidmc, warping is caused by excess heat, but to answer my own post, there is another reason for this to happen: caliper piston getting stuck, this is what happened to my bike, I already bought the disk and I will buy a new caliper, I don't want to take any chances with rebuilding the old one.
Also, I realized that the bike would be rideable in an emergency, just remove the warped disk, reinstall the caliper, pump the brake lever until the pads touch eachother, and ride to the nearest parts dealer.
Thanks,
Motor.