Latest addition to the ProX program is the Exhaust Valve & Spring Kits. This kit is offered as an alternative where the OEM application uses Titanium valves. ProX has now developed the Exhaust Valve & Spring Kits, containing a set of steel intake or exhaust valves plus a set of specially designed stronger valve springs. The ProX kit just replaces the OEM valves & valve springs and can be installed using the OEM retainers, bases and valve seals.
Features:

• Steel Valves for increased durability and less wear under extreme conditions


• Nitrided valves offer high microhardness while supersmooth surface finish reduces friction between stem and guide


• Special stronger valve springs deal with the extra weight of the steel valves


• Springs are made from premium Chrome Vanadium Steel for higher performance and durability at high RPMs


• Fully rebuildable with OEM retainers, bases and seals without the need of any further engine modifications


• Comes as complete package for quick, easy and cost efficient replacement

Fitment:
2003 Yamaha WR450F
2003 Yamaha YZ450F
2004 Yamaha WR450F
2004 Yamaha YZ450F
2005 Yamaha WR450F
2005 Yamaha YZ450F
2006 Yamaha WR450F
2006 Yamaha YZ450F
2007 Yamaha WR450F
2007 Yamaha YZ450F
2008 Yamaha WR450F
2008 Yamaha YZ450F
2009 Yamaha WR450F
2009 Yamaha YZ450F
2010 Yamaha WR450F
2011 Yamaha WR450F
2012 Yamaha WR450F
2013 Gas-Gas EC 450F
2013 Yamaha WR450F
2014 Gas-Gas EC 450F
2014 Yamaha WR450F
2015 Gas-Gas EC 450F
2015 Yamaha WR450F