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Rhun
Posted on Tuesday, June 21, 2011 - 10:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I purchased the front rotor mounting kit from Erik Buell Racing a while back. These are the ones that use the spring washers and not the long spring like stock mounts. This wheel finally made it into my dry track setup. One thing I've noticed is than when coming off the track, while putting on my tire warmers the wheel is hard to turn. Giving the wheel a mild spin it moves only 4 or 5 inches. Sounds like the pads are dragging quite a bit. Rotor temp is about 170. When removing the warmers for the next outing the wheel makes several revolutions with minimal pad drag. Through out the session brake feel and movement is good. Is this common? I don't recall this happening with the stock set up. Any ideas?
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Jdugger
Posted on Tuesday, June 21, 2011 - 10:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Normal for me. I get a lot of drag once they are hot.

Are you getting any shudder under hard braking?
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Rhun
Posted on Wednesday, June 22, 2011 - 04:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

No, braking seems normal.
I notice some clicking when I'm in the pit area. Are you using the spring mounts or the washer mount for your rotor?
Thanks for responding. I was worried about a lockup at speed!
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Jdugger
Posted on Wednesday, June 22, 2011 - 11:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I use *mostly* the new Erik Buell Racing hardware. I make a couple of subtle changes to it.

The new stuff that uses the washer/disc spring mounts is vastly superior to the old OEM mounting approach with the long springs. I recommend you switch. For me, the old OEM stuff just won't hold up or do the job. The new stuff performs generally well, though I do have some issues related to heat in the summertime.

The clicking sound is almost certainly worn drive bushings or a worn rotor itself. You probably need to replace the mounting hardware, and honestly, if it's clicking, the rotor is probably already toast.

The OEM mounting is especially prone to slightly misaligning under load, and the drive bushings and rotor bearing edges shear as much as they work as designed. This causes the drive bushings to become loose and create the clicking sound you hear. It's actually doing it on track, too, you just don't hear it, or you are using the brakes hard enough to temporarily bind the brake tight enough to not hear the noise. Give it time, it will soon do it on every stop.

Go ahead and pull your rotor from the wheel and carefully inspect the bearing edges. If they aren't perfect -- honestly if they show much wear at all and certainly if they show any shear -- replace it.

Use the Erik Buell Racing mounting hardware kit. It's significantly better at just about everything unless your are one of the unlucky ones that has an OEM wheel on the edge of tolerance. I've got a solution for that, though. If you get shudder with the new mounting kit, I'll send you a McMaster part number for some slightly different washers that will float the rotor slightly more at the expense of needing to service the disc springs more frequently. But, it will stop the shudder.

Honestly, the OEM brake kit stuff just isn't up to the task of the speeds the 1125r can generate on track with either a rider that's good on the brakes or on a braking oriented track. You will get better brake performance and much improved service life out of the newer kit.
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Rhun
Posted on Thursday, June 23, 2011 - 05:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thanks for the advice, but I am using the Erik Buell Racing mounting kit. I will put a dial indicator on the wheel at the mounting points and shim accordingly. The rotor is fairly new I think, but I'll look for a ridge. I don't hear the click when I leave the pits only when I return. To me the drag seems substantial, when coming into the pits.
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Jdugger
Posted on Friday, June 24, 2011 - 07:47 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Oh... I missed that! Sorry for being a non-reading doosh.

Here's something for you to try regarding the drag if it's really ridiculous. (and, btw, mine do drag an awful lot, too...but this helps)

Replace the copper washer in the kit with this part. McMaster #94397A478 This is a thinner washer, and will give the rotor about .012 more float than the Erik Buell Racing part.

Now, you may notice that after races or hot track days when you really use the brake hard the disc springs will anneal and the rotor becomes a little loose. With the Erik Buell Racing kit, the rattle/float is less than once you replace that copper washer with a thinner one, so you need to keep an eye on it. When the rotor is loose, replace the disc/washer springs with this part: 9712K69

When servicing the hardware, I've had good luck using a cutting tap to clean out the threads of the wheel. I use my BARE HANDS to turn the tap with no drive tool. Then, I use loctite blue on the fastener. I have a tap I bought brand new that I've never used for cutting that I use to clean out the gunk from the fastener locker.

These changes *should* help your brake drag (it does mine) at the expense of slightly worse heat handling because of the smaller copper washer, and the need to service those disc springs more often if you run the brake really hot.

BTW: I should probably disclose these are not engineered solutions. This is just good 'ol Texas redneck testing at work. But, I've had some pretty significant heat issues with the brake and these changes have seemed to help with both drag and rotors warping and shuddering under high brake loads.

As for the clicking, I'm still almost confident, even not seeing the bike, that it's the drive bushings that have worn. If there's any play in your rotor at all at human hand pressures I'm absolutely confident of it. I get this same clicking -- correlated to vehicle speed -- at lighter braking pressures. When I do, it means it's time for new drive bushings, and possibly a new rotor. It will get worse.
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Rhun
Posted on Friday, June 24, 2011 - 04:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thanks again. I'll play with this tonight!!
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Rhun
Posted on Wednesday, July 06, 2011 - 11:10 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

A few 'what I founds'
When I assembled the rotor with the Erik Buell Racing race kit I inadvertently got the steel washer off center so that it crimped the end thus 'welding' the washer to the 'stud'. I.e. no float. The clicking came from the rotor not being centered. As it heated the brake backing got closer to the bolt head. The rotor didn't center because it was locked into place from the washer. This also caused the rotor to be farther out during part of the revolution. Using a dial indicator I also found that the wheel mounting points weren't completely parallel. So I'll adjust with a file. As my rotor was within tolerances .0177 barely and had major discoloration and some scoring I've ordered a new one. As I screwed up the copper washer getting the steel washer off, Erik Buell Racing was kind enough to send me a couple new ones. Erik Buell Racing thoughts were that the EBC pads may be warping. I don't know if they are basing this on the FA345 (stock), the GFA345 the old racing or the new EPFA345 racing. I will heat them in the oven to 170 and see what happens with warp age if they appear flat when I take them off.
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