STL INT VALVE/SPRING KIT RM-Z250 '07-11 28.SIS3338-2

Replaces the OEM valves & valve springs

Steel, nitrided valves for increased durability and less wear under extreme conditions

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 rpm

Kit contains a set of steel intake or exhaust valves plus a set of specially designed valve springs; can be installed using the OEM retainers, bases and valve seals