turning rotors

[quasi2008]

considering that new rotors are about $215. ea, anyone had theirs put on a brake lathe and dressed up? mine aren't real bad, just some light grooving.

[WingAdmin]

considering that new rotors are about $215. ea, anyone had theirs put on a brake lathe and dressed up? mine aren't real bad, just some light grooving.

Bike rotors are not like car rotors. They are extremely hard, and not designed to be turned. Not only will most automotive lathes not fit the rotors in the first place, most of the lathes won't actually machine bike rotors, because the rotor material is so hard.

There is one place online that has specialized equipment to machine bike rotors, but it's not cheap.

Because bike rotors are so hard, they are designed to not wear the way automotive rotors are. And because of this, the tolerances are very small - it does not take much wear on a bike rotor to bring its thickness below minimum limits.

Incidentally, this high carbon content steel used for bike rotors is one of the main reasons for their high cost.

[quasi2008]

thanks for the info.

[winguyjo]

good golly, miss molly ... so glad i read this !
i have a set of wheels that i was going to let go for very little money, with rotors still attached.
i think i am going to store them under my mattress now until i need them !

[virgilmobile]

This is the reason to use OEM brake pads.Cheaper to replace them often rather than one rotor just once.
Same for my truck.

[DaveO430]

If the rotors are not warped and still above minimum thickness use them, grooves won't hurt anything.

[CrystalPistol]

If the rotors are not warped and still above minimum thickness use them, grooves won't hurt anything.

Even with car rotors on my several police cars, never turned them to smooth out grooves, pads will wear to fit grooves fast anyway.

Only time I have had rotors turned was when warped bad … and that was a short fix. Still had to replace them.

[DenverWinger]

A little off-topic, but a race-car driver friend gave me a hint to stop brakes from squeaking on my 1100.. I guess they do this on race cars.... The '80 1100 has solid rotors (no slots or holes in the brake surface) and the brakes would squeal like hell when applied. I guess the slots and holes help with the squealing. I suppose OEM pads wouldn't do that on solid rotor but those are scarce. He said to take a die grinder and put some serious radial scratches in the brake surface on one side. I took the front rotors off and scratched them up on the inside surface, and the rear brake I just scratched up where I could get to it with the wheel on the bike, looks kinda ugly but rotor is mostly hidden by saddlebags and whaddya know - IT WORKS!. Lasts a couple seasons until you finally wear out the scratches and the squeaking returns. Just do it again, you will probably be replacing pads at that time anyway.

[quasi2008]

makes sense to me. think i'll give it a shot.