On my 03 I just did a rough measurment and came as close as I can without taking the wheel off. From the left swing arm flang to the disk brake (so overall hub width) is about 6 7/8in and I think this is the measurment you need. If you are just looking for the spoket to the disk it is 6 5/8. Keep in mind this was all on the bike so its not exact.
Originally Posted by kpt4321
To add some data to this thread:
My 2006 TE 610 wheel has roughly 6.25 inch spacing between the centerlines of the rotor and sprocket.
Anybody have a previous generation bike (with cush drive hub) that they can measure?