How do I make my 600 fazer faster?????

[stevierst]

I used to do quite a bit of engine tuning in my younger years, swapping cams, porting heads, bigger carbs etc....... It rarely makes the bike "better" for the road, peaky power delivery, boggy at the lower end, stupidly high tickover that's lumpy as fook, nightmare to ride in traffic. Overheating, unreliability, the list goes on.
You'll gain a little power by cams/head tuning, but won't necessarily make the bike faster. The best tuning you can do, is get the suspension sorted, then some advanced training, or track tuition. THEN it'll be a lot quicker! You watch a good rider on a 400 hit the twisties, he don't need massive power, just big skill!