Ferrea 03-09 Yamaha YZF450 5V 13.3mm ID 38lbs at 29.5mm Seat Press Single Valve Springs - Set of 5

These Ferrea valve springs are built with a 13.3mm inner diameter and are designed to provide 38 pounds of pressure at a 29.5mm installed height. This specific spring rate is crucial for maintaining proper valve control, especially when you're pushing your 2003-2009 Yamaha YZF450's engine harder than stock.

Ferrea uses a high-tensile wire for these springs, which helps them withstand the repeated stress of opening and closing valves at higher RPMs. This well-built construction means they'll hold their seat pressure consistently, preventing valve float and ensuring your engine runs smoothly and reliably. You get a set of five springs, enough for one cylinder, so you'll need to order accordingly for your entire engine.