Warped rotor repairable?

[Jerambelu]

I apologize if this issue has previously been discussed on this forum, but I came up empty handed when I conducted a search.

Ok, a little back story...a few months ago my '05 blew a fork seal, which lubed up my right side rotor and pads, causing the left side to carry the majority of the braking burden. After repairing the forks, I cleaned up the brakes and threw on a new set of EBC Organic pads.

Life was good for a few weeks, but then front brakes began to shudder under all but the lightest of braking applications. So I took out my dial indicator to determine if I had a warped rotor, and which one it was. It turns out the left side is warped, which is logical since it was doing all the braking for a hundred + miles with a lot of stops. Anyway, so the dial indicator revealed I had about .0045" of run-out. According to the service manual, 0.1 mm (.00393701") of run-out is the maximum allowable.

Being the cheap (and broke) bastard that I am, I decided I'd try to correct the warpage by applying some leverage on the rotor at the peak point of run-out. After a couple of minor tweaks utilizing a very little force, the rotor was within .001" of run-out. I took the bike out this evening on about a 20 mile loop and tested the brakes, and was pleased to feel they were silky smooth!

The question I have, has anyone else had any experience with this? I am concerned that with several heat cycles the metal will want to revert to its previously warped state.

Thanks in advance guys!

 

[Canadian FJR]

There is a real creative metal guy (welder) that has done them here locally. I sent him my rear one but mine was repaired simply by a light grinding/buffing. It was created by a lot of wet weather riding on one specific trip and the crud baked on to a few spots making it seem like a warp.

Good luck.

Canadian FJR

 

[redjay]

"I am concerned that with several heat cycles the metal will want to revert to its previously warped state".

Anything is possible, maybe the several heat cycles will stress relieve the rotor and it will stay straight ?

There is only one way to find out.

 

[RossKean]

You were only marginally outside the allowable limit. Gentle persuasion with levering it back into place or a few raps with a rubber hammer is certainly what I would try if the warpage was causing any issues with pulsating brakes (assuming it wasn't way out of spec). If it goes back to the way it was, what's the problem? Repeat the process if necessary. I doubt that it is a safety issue.

On the EBC organic pads; they may be OK but don't expect the stopping power or the longevity of the HH. Some people have claimed that the HH eat rotors and don't last but I have been running them (2 sets) for 75,000 miles without issues. (Gen II) Yamaha wants an obscene amount of money for the OEM fronts so I went with aftermarket pads - probably would have bought OEM if I had a Gen I.

 

[900gc]

You were only marginally outside the allowable limit. Gentle persuasion with levering it back into place or a few raps with a rubber hammer is certainly what I would try if the warpage was causing any issues with pulsating brakes (assuming it wasn't way out of spec). If it goes back to the way it was, what's the problem? Repeat the process if necessary. I doubt that it is a safety issue.
On the EBC organic pads; they may be OK but don't expect the stopping power or the longevity of the HH. Some people have claimed that the HH eat rotors and don't last but I have been running them (2 sets) for 75,000 miles without issues. (Gen II) Yamaha wants an obscene amount of money for the OEM fronts so I went with aftermarket pads - probably would have bought OEM if I had a Gen I.

Good to know about the HH pads. I've always preferred them over organic for the increased stopping power. Looks like I'll go that route when the time comes.

What brand did you go with?

 

[RadioHowie]

You were only marginally outside the allowable limit. Gentle persuasion with levering it back into place or a few raps with a rubber hammer is certainly what I would try if the warpage was causing any issues with pulsating brakes (assuming it wasn't way out of spec). If it goes back to the way it was, what's the problem? Repeat the process if necessary. I doubt that it is a safety issue.

On the EBC organic pads; they may be OK but don't expect the stopping power or the longevity of the HH. Some people have claimed that the HH eat rotors and don't last but I have been running them (2 sets) for 75,000 miles without issues. (Gen II) Yamaha wants an obscene amount of money for the OEM fronts so I went with aftermarket pads - probably would have bought OEM if I had a Gen I.

Good to know about the HH pads. I've always preferred them over organic for the increased stopping power. Looks like I'll go that route when the time comes.What brand did you go with?

I'm guessing "EBC"?

 

[Afast03nNJ]

The run out wasn't causing the vibrations (brake judder). Brake vibrations are caused by pad material transfer. It can be corrected, but running the correct pad for your application will prevent it from happening.

Read more here:

https://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

 

[900gc]

You were only marginally outside the allowable limit. Gentle persuasion with levering it back into place or a few raps with a rubber hammer is certainly what I would try if the warpage was causing any issues with pulsating brakes (assuming it wasn't way out of spec). If it goes back to the way it was, what's the problem? Repeat the process if necessary. I doubt that it is a safety issue.

On the EBC organic pads; they may be OK but don't expect the stopping power or the longevity of the HH. Some people have claimed that the HH eat rotors and don't last but I have been running them (2 sets) for 75,000 miles without issues. (Gen II) Yamaha wants an obscene amount of money for the OEM fronts so I went with aftermarket pads - probably would have bought OEM if I had a Gen I.

Good to know about the HH pads. I've always preferred them over organic for the increased stopping power. Looks like I'll go that route when the time comes.What brand did you go with?

I'm guessing "EBC"?

Well he mentioned EBC organic pads and it would be a logical assumption that he is using the same brand in HH. Just want to make sure.

 

[Queensland Ken]

Did a service on my mates bike today, yep, his RHS rotor is slightly warped.

Didn't have a dial gauge to check the run out.

The rotors are semi-floating on the FJR's and should have a slight movement, not stuck solid.
Freed up the bobbins / buttons / rivets using the trusty nut/bolt method and a bit of brake clean.

 

[Jerambelu]

The run out wasn't causing the vibrations (brake judder). Brake vibrations are caused by pad material transfer. It can be corrected, but running the correct pad for your application will prevent it from happening.
Read more here:

https://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

Thanks, very informative. The studder has reappeared, though only slight, so this gives me some hope that I wont be spending $300 on new OE rotors. I think I might scrub the rotors down with some garnet paper and install some fresh semi-metallic pads.

 

[dsmack]

That was a very informative and well written article. Filed that one away for future reference!