Smooth radius dome and dish designs. Radiused valve reliefs. Precision CNC machined ring grooves. Machined oil drain back holes engineered for specific oil control. Factory honed pin bores, wrist pins and locks. Pro Series features reduced weight and dedicated forgings.
Yamaha YFZ450 2012-2013
Yamaha YFZ450 2006-2009
Yamaha YFZ450R 2009-2017

Warning: Cancer and Reproductive Harm –
www.P65Warnings.ca.gov