from my understanding, rex, and bill are right. i have gone down one tooth in the front, so instead of 16/44 i have 15/44. i didnt go up in the rear because i dont want to give up the top end speed. in another fourm the recommended change for the fz1 is -1/+3. the downside to the change is that the front tire doesnt want to touch asphalt until 3rd gear.
another thing is that when you change the sprockets at all, you will have a speedometer that is inaccurate. again, on the fz, there is a -5% change in measured speed at the speedometer. this means that reflected miles, and speed are wrong on the gauges. you can buy devices, such as a speedohealer to fix the problem, or just live with it, as it isnt really a big deal until you try to sell it. (high mileage=lower resale)