Have you done any airbox/air filter work? I would recommend drilling some 1" holes in your airbox lid to make the most of your pipe.
As far as jetting goes....there is a 17mm plug you will see on the bottom of the float bowl, take that out, and get a 6mm socket and take the main jet out. It takes about 5 minutes to change the main jet. BTW it's a good idea to drain the fuel out of the float bowl first... Good luck.
2000-440ex Stroker--Fan Cooled
Houser +1 A-Arms, Elka Triple rates, Laegers +1 1/4 Swingarm, G-Force Axle w/Durablue Anti-Fade Locknut, 14/36 Gearing, DID X-Ring Chain, C&D Revalved Rear, Maier Silver Plastic, Steel Grey PCed Frame, SPAL Fan, AC Bumper, Pro Armour Footpeg Extensions, Renthal Bars, Yoshimura Full Exhaust, 450R Carb w/ZR's Adaptor, K&N w/o Lid, Powroll 440 Stroker w/stg 3 HC, P&P Head, HD rod, GT Thunder HD Studs, and Timing chain, AMR Monster Coil, 4 Degree Advance Key and a 12oz lighter flywheel. Now at 12.5:1 Compression!
450R Front brake upgrade using 06-up Spindles and 07' hubs.
450R Rear Brake Upgrade
Kenda Knarly XC Radial 21x11x9 Rear Tires
Shorai Lithium Iron Battery
Running E85--Jetting: 70 pilot, 240 main, HRC needle on bottom notch and shimmed.