The ProX Exhaust Valve and Spring Conversion Kit, manufacturer part number 28.SES4409-1 and vendor part number 19-9516, provides a durable steel-valve replacement for Kawasaki KX450F models that originally use titanium exhaust valves. This complete conversion set is designed for 2009 through 2018 Kawasaki KX450F applications and includes steel exhaust valves with specially developed stronger valve springs.
Nitrided steel valves offer increased microhardness and a smooth surface finish to help reduce friction between the valve stem and guide. The stronger springs are manufactured from premium chrome vanadium steel to accommodate the additional weight of steel valves while supporting reliable performance during high-RPM operation. This design helps improve durability and reduce wear under demanding riding and racing conditions.
The ProX kit is designed to replace the original equipment valves and valve springs while retaining the OEM retainers, spring bases, and valve seals. No additional engine modifications are required, making the kit suitable for a straightforward, cost-efficient top-end service. It is supplied as a complete package for quick installation and dependable exhaust-valve replacement.
Fitment includes the 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, and 2018 Kawasaki KX450F. Confirm engine application and existing OEM components before installation to ensure proper compatibility.
Features:
- Durable steel exhaust valves designed as an alternative to OEM titanium valves
- Nitrided valve surfaces provide high microhardness and reduced friction between the valve stem and guide
- Specially designed stronger valve springs compensate for the additional weight of steel valves
- Premium chrome vanadium steel springs support durability and performance at high RPMs
- Installs using OEM retainers, spring bases, and valve seals without additional engine modifications
- Complete valve and spring package for efficient replacement and engine rebuilding
- Fits Kawasaki KX450F models from 2009 through 2018
Fitment:
2009 Kawasaki KX450F
2010 Kawasaki KX450F
2011 Kawasaki KX450F
2012 Kawasaki KX450F
2013 Kawasaki KX450F
2014 Kawasaki KX450F
2015 Kawasaki KX450F
2016 Kawasaki KX450F
2017 Kawasaki KX450F
2018 Kawasaki KX450F