Well I took nearly a full pound out of my Impact with the following:
1. Change the wing tube to a carbon tube from Jerry Budd
2. Changed the exhaust from a 2c hatori pipe to a carbon Aeroslve pipe
3. Had Ryan M. build me a new nose ring and use the Hyde mount w/o the nose ring integrated with it.
4. Use light wheels

All the little items you don't give much thought to really add up in a hurry if you change them all.

Good luck!

Joe W.