Honning/resurfacing brake rotors

**Sal_R1** · 05-20-2011, 11:50 AM

On a car its common place to resurface rotors (within specs) when replacing the pads. Eliminates brake squeak, improves braking by optimizing pad to rotor contact, smooths out warped rotors etc....

Im thinking about honning my bike rotors for the same reasons. I understand that its a thinner rotor to start with so i will take a minimal amount off. I have semi floating rotors so the buttons are coming off & the rotor itself is going to be held by a home made jig (a turning table) with a Flex hone meduim grit wheel for the honning.

Has anyone done anything like this before & how?

**Sal_R1** · 08-10-2011, 10:41 PM

TTT.........

markjenn · 08-11-2011, 03:04 AM

Resurfacing of motorcycle brake rotors is not commonly done and I've only met one shop that said they have ever done it. No motorcycle disc mfg that I'm aware of recommends machining motorcycle rotors and motorcycle service manuals generally say that if a rotor won't meet spec that it should be replaced.

Your analogy to cars doesn't carry very far because car brake rotors are made out of cast iron while motorcycle rotors are made from heat-treated stainless steel. (There have been a few cast iron motorcycle brake rotors over the years, but they are very uncommon. I've heard that cast iron is preferable from a braking standpoint, but cast iron rusts and discolors so it is not acceptable from an appearance standpoint for a vehicle in which the discs are so visible.) Car brake discs are used turned in a lathe with cutting tools used to remove material, but this won't work at all with stainless steel.

One guy I know who does wheel repairs says he will occasionally resurface motorcycle rotors to get rid of the glaze and improve appearance, but it requires special grinding stones. He also says that any significant grinding typically takes a motorcycle disc below minimum thickness so he doesn't recommend it from a performance standpoint - he does it on classics to make the brakes look new again.

All in all, I see very limited benefit to what you are considering and a lot of risk you'll do more harm than good. It certainly is not SOP during brake refurbishment.

- Mark

skapan · 08-11-2011, 06:15 AM

I don't see why you can't use those honing wheels on a motorcycle disc. It's not like you're removing any significant amount of material. Bear in mind that if there are hard spots or the rotor is warped, I doubt that this treatment will make any difference. Provides a nice finish by the looks of things, but that's it. Why not?

Nikk777 · 08-11-2011, 09:30 AM

Get some 200-400 grit sand paper, "pinch" the rotor with the sandpaper on both sides and spin the wheel several times. This should remove enough old material from the previous pads to allow your new pads fresh surface area for proper bedding.

crabman · 08-11-2011, 11:16 AM

Quote:

Originally Posted by Nikk777

Get some 200-400 grit sand paper, "pinch" the rotor with the sandpaper on both sides and spin the wheel several times. This should remove enough old material from the previous pads to allow your new pads fresh surface area for proper bedding.

+1

I've done this for years, just cleaning the surface with light sandpaper and the new pads will seat in well.

Koby · 08-11-2011, 12:09 PM

Wow is this thread a joke?

Don't touch your rotors they are fine. Unless they break into pieces, are damaged from a fall, or warped beyond the point where you can control braking than for the love of god don't touch them. If any of those conditions were met you just replace they are that cheap.

Trust me, you are not going to warp your factory rotors and they do not need re-surfaced.

**Sal_R1** · 08-12-2011, 02:03 PM

When optimal braking is achieved by the rotor & brake pad surface being as perfectly matched as possible "flat surfaces" on what basis would you find this funny?

Its common sense that only the minimum amount of rotor material should be removed to achieve that flat surface!

Aaaaaaaaaaand you havnt seen my rotors! lol...... Have 65K on them with very slight "ridges" that can only be felt by touching the rotor, no warps etc....

Quote:

Originally Posted by Koby

Wow is this thread a joke?

Don't touch your rotors they are fine. Unless they break into pieces, are damaged from a fall, or warped beyond the point where you can control braking than for the love of god don't touch them. If any of those conditions were met you just replace they are that cheap.

Trust me, you are not going to warp your factory rotors and they do not need re-surfaced.

Alterego · 08-12-2011, 04:09 PM

For the R1 I assume. Personally I would not do it, they are common and cheap enough off Ebay. I have a used set with about 10k miles I'll give you.
They are off an 01 R1.

Quote:

Originally Posted by Sal_R1

When optimal braking is achieved by the rotor & brake pad surface being as perfectly matched as possible "flat surfaces" on what basis would you find this funny?

Its common sense that only the minimum amount of rotor material should be removed to achieve that flat surface!

Aaaaaaaaaaand you havnt seen my rotors! lol...... Have 65K on them with very slight "ridges" that can only be felt by touching the rotor, no warps etc....