Suspension Fluid

About

The right suspension fluid is a foundational element of chassis performance, not an afterthought. Putoline GPR6 and Motul Factory Line shock oils give you the viscosity control needed to match your suspension setup to your riding conditions and rider weight. How to Choose Motorcycle Suspension Fluid Suspension fluid viscosity directly determines damping response. A fluid that is too thick slows damping speed; too thin and your fork or shock cycles without control. The SAE viscosity grade printed on every bottle is your starting point, and matching it to your OEM specification or tuner's recommendation is the single most important step you can take. Putoline GPR6 vs Motul Factory Line: Key Differences Property Putoline GPR6 Motul Factory Line VI400 Available weights 2.5W, 3.5W Single SAE grade Viscosity Index Standard mineral base VI 400 (very high VI) Primary application Shock absorbers Shock absorbers Bulk option Available in 20 L 1 L only Brand origin Netherlands France Viscosity Grade Explained The "W" in 2.5W and 3.5W indicates a winter-grade viscosity measured at low temperature. Lower numbers mean thinner fluid and faster damping response at cold temperatures, which suits lighter riders or cooler climates. A 3.5W fluid provides more resistance per stroke, suiting heavier riders or riders who prefer a firmer mid-stroke feel. Most OEM rear shock specifications fall between 2.5W and 5W, so both GPR6 grades cover the majority of road and off-road applications. Motul VI400 Technology A Viscosity Index of 400 means the fluid resists thinning as it heats up across a service cycle. Standard mineral shock oils typically carry a VI of 90 to 120. At VI 400, the Motul Factory Line fluid maintains consistent damping force from a cold start through a full track or enduro session, reducing the fade that can occur when standard fluid thins under heat. When to Change Suspension Fluid Most manufacturers recommend a shock oil service every 2 years or 20,000 km, whichever comes f