Maxima Racing Fork Fluid

Maxima Racing Fork Fluid is a high-viscosity-index (VI) suspension fluid engineered specifically for modern cartridge, inverted (USD), and conventional open-bath motorcycle forks. Under aggressive trail or track riding, rapid cycling of fork shim stacks generates significant internal heat and mechanical shear. Standard hydraulic oils experience viscosity breakdown and oil aeration under these conditions, causing erratic rebound damping, harsh mid-stroke response, and premature seal wear.

Formulated with premium petroleum base stocks and a shear-stable polymer system, Maxima Racing Fork Fluid maintains consistent hydraulic dampening across wide operating temperatures. It incorporates proprietary anti-wear additives and "Lubricinol" surface-active agents that condition elastomer seals and coat internal bushings, reducing stiction (static friction) for smooth initial breakaway action. Advanced anti-foam chemistries eliminate fluid cavitation and air entrainment, ensuring consistent valving response from the first mile to the end of the moto.

Features:

• High Viscosity Index (150+): Maintains stable hydraulic damping rates across high-temperature cycles without thinning out or fading.

• Anti-Stiction Lubricinol Technology: Reduces static and sliding friction between fork sliders, internal bushings, and oil seals for supple small-bump compliance.

• Zero-Foam Formulation: Anti-foaming additives prevent air cavitation and emulsification inside high-velocity damping cartridges.

• Seal Conditioning Chemistry: Prevents hardening, shrinkage, and micro-cracking of NBR and FKM fork seals to minimize weeping and oil leaks.

• Shear-Stable Base Oils: Resists mechanical shear forces generated across high-speed compression and rebound shim stacks.

• 100% Miscible for Custom Tuning: Viscosities can be intermixed in calculated ratios to create intermediate weights (e.g., mixing equal parts 5wt and 7wt yields a 6wt fluid).

What's in the Box:

• 1x Maxima Racing Fork Fluid (1-Liter / 33.8 fl oz Bottle)

• (Note: Select your required viscosity—5wt, 7wt, 10wt, or 15wt—from the variant dropdown menu before checkout).

Viscosity Selection & Application Guide:

• 5wt (85/150): Standard factory OEM replacement weight for most modern motocross, cross-country, and enduro closed-cartridge and dual-chamber forks (WP XACT, KYB SSS, Showa Twin Chamber). Ideal for light valving resistance and fast-acting response.

• 7wt (125/150): Common factory specification for European dual-sport and enduro open-bath forks (WP XPLOR, Marzocchi, Sachs). Provides slightly firmer compression and slower rebound damping than 5wt.

• 10wt (165/150): Recommended for damper-rod forks, conventional dual-sport forks (Suzuki DR-Z400, Suzuki DR650, Kawasaki KLR650), and heavier middleweight/adventure applications requiring increased low-speed damping firmness.

• 15wt (235/150): Formulated for vintage damper-rod forks, road bikes, and heavy touring front ends where stiffer front damping and slower rebound are required to manage chassis pitch and heavy springs.

  • Fluid Viscosity (Weight): Controls the speed at which fluid moves through the valve shims and orifices across theentire stroke. Increasing viscosity increases both compression and rebound damping stiffness.
  • Oil Height (Air Chamber): Controls the size of the trapped air spring inside the fork tube, which dictatesend-stroke bottoming resistance. If your fork valving feels plush throughout the travel but bottoms out hard on flat landings or g-outs, do not increase oil viscosity; raise the oil level by 5–10 mm to ramp up final bottoming resistance without stiffening small-bump compliance.
  • Tuning Viscosity vs. Tuning Oil Height: Viscosity and oil height alter two completely different suspension characteristics:
    
    

• Linear Miscibility for Custom Weights: All Maxima Racing Fork Fluids share the exact same base chemistry and additive package, making them fully miscible. If 5wt yields a fork that dives too rapidly on corner entry, but 7wt feels too harsh over square-edge chop, you can blend a 50/50 mixture of 5wt and 7wt to create a true 6wt fluid. Mix ratios are linear: 75% 5wt and 25% 7wt yields a 5.5wt fluid.

• Cartridge Purging & Bleeding: When refilling closed-cartridge or open-bath dampers, pump the damper rod slowly through its full stroke 10 to 15 times until all resistance is smooth and air bubbles stop breaking at the surface. Rapid pumping forces micro-bubbles into the valve orifices, creating fluid emulsion that requires hours of sitting to settle out. Always verify that internal cartridges are fully bled before setting the final air gap or closing the top caps.