There are many heavy components on a 750 that can go on a diet (but many of these are not cheap mods):
Steel rims vs. re-lacing with aluminum rims
Stock seat vs. aftermarket/custom aluminum
Steel gas tank vs. custom aluminum
Stock 4-4 exhaust vs. aftermarket 4-1
Stock wiring harness vs. custom
Stock lights vs. aftermarket
Stock shocks vs. aftermarket Race Tech, Works, Fox
Elimination of centerstand, chain guard, rear sprocket guard, fenders, electric starter