KTM supermoto wheels issue

I purchased a set of the KTM 17" wheels for my DRZ last week. I know that they need custom spacers to fit correctly. These wheels came off of another DRZ so the spacers are close to right but I still need to tweak them a bit because the front wheel is still off by about 1/8" when measuring distances from the rim to the fork tube (closer to the brake side if that matters). I can manage these spacers just fine, my real question is this: The front brake is that big floating KTM disk with no slotting or holes or anything, just a solid disk. The braking surface on that disk seems a lot larger then the stock rotor but after running the wheels for a bit I am worried about how much of the disk is actaully contacting the pads.

HERE is a photo of the front wheel showing the disk. http://groups.msn.com/_Secure/0UgAAAMsaAYVOUdf5A7hO3sZ1EIzYKu*3GBrPEoRlb0sDdwlm0VJRXC!17Ts*je8wHRT0QPBBJ*wZK8qYIOmXeiUt6KMkEKTUPqVtPA6jikHNcP9yDwF7O4vD*V8XVqOk/wheel.jpg?dc=4675544056997129923

I don't have the caliper bracket with me right now but I am thinking that the braket is meant for a disk that is a few mm larger so it might be setting it out a little too far for the correct contact on the disk.

Your thoughts?

Looking at the disc means nothng. Are the pads in full contact? As long as all of the pad surface is on the disc, it is fine and the way it should be.

OK. I am back where the wheels are and this is what I have learned.

The disk measures to 308mm+/- so I am going to call that a 310 mm disk.

The ONLY caliper adapter that I see availible from "Braking" is for a 320mm disk (that is the adapter that I have).

When looking at the pads, you can see that ~5 mm of that pad is not contacting the disk because it is too far off the surface.

We can then do the math and see that 5mm of unused pad means that the caliper is mounted for a 320 because the 5mm unused pad (radius) times 2 equals 10mm which is the differnce between a 310 and a 320 rotor (duh).

Next questions:

Is there any significant differnce in stopping power to be realized by grabbing that last 5mm?

Anyone know of a 310 mm adapter for the DRZ?

Should I just quit my bitchin and run it?

I was expecting a huge differnce over the stock rotor but honestly I wasn't as impressed as I was hoping. There is a very noticable difference over the stock but its not as effortless as I was expecting. I am thinking that a change in pad compound would help also. That will about do it for now.

To make the 310mm work on the DRZ you would need a custom made adapter or get some DRZ400SM forks which have the stock fork collets setup to move the caliper out for a 310mm disc.

Just get a 320mm disc for a KTM and call it good. :banghead:

The thing I would worry about is as the pad wears the part off the disc will contact pad to pad and then you have no brake. Try HH compound pads for more grab. I woud move the caliper to get all the pad on the disc.

What kind of caliper? Piston size? What master cylinder? Piston size? The Hydraulic ratio is wha gives you the 1 finger brake.

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