SGrind, you can drop the bowl and check them. The # is etched into the jet. This way, you get familiar with the insides of your carb (if you aren't already) before you start swapping stuff.
What else you going to do? Adding a K&N filter too right? Make sure you take all those mods into consideration when figuring a jet combo and also remember that every bike & motor is a little different. What works for one, may not be what works for you. It will prolly get you in the ball park but your motor will tell you what it needs (and so will a dyno!

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