7000.00 you could buy alot of parts to make that thing un-rideable, with the kind of hp you could make for that kind of money, 21 lds wouldn't make any difference.
Reduce rotating mass, instead of static mass, that will save some power! switch to PTR pipes (stingers & silencers are aluminum), change motor mounts and other brackets to aluminum or titanium, switch your fasteners to titanium, rear brake, sprocket, & wheel hubs can all be changed to alum., Titanium chain, alum, or tri metal sprockets, losse the lighting, extra stud lengths, wires, & plastics, not to mention all the tors, air box & e-brake crap.
I'll bet with those changes you save yourself way more than 20 lbs and for a heck of alot less than 7g's.