2006-2008 Yamaha RS, Vector, Rage Factory Service Manual, Page 75Get this manual
CARBURETOR TUNING
INSP ADJ
A Standard main jet Main jet whose diameter is 10 smaller than standard Main jet whose diameter is 10 larger than standard
CAUTION:
If the air filter case is removed from the carburetors, the change in pressure in the intake will create lean mixture that may cause severe engine damageThe air filter case has no effect on performance characteristics and must be secured to the carburetors during carburetor tuning and adjustmentAlso, it must always be in place when the engine is operatedRegularly clean the air filter and keep it free from obstructions
Low-speed tuning The carburetors are built so that low speed tuning can be done by adjusting the pilot screw and throttle stop screw 2