To start with, open airbox with dynojet and open pipes. Then Keihin 41mm flat-slide carbs. That will cost in the region of £1200 + fitting. You might get 7-10bhp from it. The flywheel, the big bore kit, the ... you name it.
It still won't go as quick as a 748 or a 600 jap il4 - close but still not as quick. If you like the bike and intend to keep it then spend the money on it.
What really counts though is when you can go quicker than a 748 and 600 on a 75bhp 2 valve
