Yep, it's always a bit scary throwing out some guesses on jetting when someone is entering "unknown territory". My '83 Vmax service manual has a good section on finding the "rich limit" on jetting, that may be worth passing along. Of course, this is starting with a stock sled with stock jetting and the clutches in good operating condition.
It suggests increasing the main jet size, a step at a time, and making some 100 meter (dang foreigners) accelerations....with the motor properly warmed up 1st!! Continue to increase the main jet size until the motor will no longer reach it's full shift RPM...then you know you have reached the "wall". Then back down 1 size and use piston wash and plug color to show the need to go down anymore with the jetting. As Tory pointed out...be careful at first.