Designed to improve throttle response, drivability and power when used in conjunction with GYTR exhaust systems and removal of airbox lid. Includes new needle (richer than stock), main jets (#152, #155, #158, #160, #162, #165, #168 and #170) and pilot jets (#40 and #45).

Fits:

• 2004 – 2008 YFZ450 Hypersports