Well my intention is to make the 750 my "rider". The 450 just does not cut it on the interstate. It keeps up fine but an hour in and my whole body is numb and it gets really wound up, like 7000-8000 rpm cruising. Its going to go on out of state trips so I would like a little more oomph for interstate riding passing at high speeds etc (anyone who's been on i-75 FL or ATL knows what I mean.) and so I could keep the rev's down a little. Not trying to make it a works engine or anything. Just figured since the kits were cheap on ebay and I'm already gunna have the engine out, why not give it a go eh?