Can't remember the guy's name, but a few years ago he turned my LTZ470 Flywheel down and took off 10oz...its still on my Zuk today...worth a try...he charges $55 shipped back to your door...can't beat the price....would have to see what he can actually do with the 525 rotor...found their link
http://www.procycle.us/main/flywheel_lightening.htm
Pro Cycle
2101 W. 10th Ave. #B
Eugene, OR 97402
541 688 9543
800 496 5516
http://www.procycle.us/main/flywheel_lightening.htm
Pro Cycle
2101 W. 10th Ave. #B
Eugene, OR 97402
541 688 9543
800 496 5516