PROX Steel Intake Valve and Spring Kit for Yamaha YZ450F (2003-2009) & WR450F (2003-2011) – Part Number 28.SIS2424-2

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

Upgrade your Yamaha YZ450F or WR450F with the PROX Steel Intake Valve and Spring Kit, designed for models from 2003 to 2009 for the YZ450F and 2003 to 2011 for the WR450F. This comprehensive kit ensures optimal engine performance by providing durable, high-quality components built to withstand the demands of competitive riding and demanding terrain. The kit includes everything necessary to replace worn or damaged intake valves and springs, helping to restore engine efficiency and power output.

Designed with precision and quality in mind, the PROX steel components offer enhanced durability over OEM parts, reducing the risk of failure during intense riding sessions. The steel construction ensures longevity and resistance to wear, providing reliable performance over extended use. This kit is an essential upgrade for riders looking to maintain peak engine performance or restore their motorcycle to factory specifications.

Installation is straightforward for experienced mechanics or skilled enthusiasts, making it an ideal choice for bike rebuilds, maintenance, or performance tuning. The part number 28.SIS2424-2 guarantees compatibility with the specified Yamaha models, ensuring a perfect fit and optimal function. Trust PROX’s reputation for quality and precision engineering when selecting parts for your motorcycle's intake system.

Features:

• Contains intake valves and springs for Yamaha YZ450F (2003-2009) and WR450F (2003-2011)

• Steel construction for enhanced durability and longevity

• Designed to restore and improve engine performance

• Precise fitment with part number 28.SIS2424-2

• Ideal for maintenance, rebuilds, and performance upgrades