AMSOIL 10W-50 100% SYNTHETIC DIRT BIKE OIL

AMSOIL 10W-50 100% Synthetic Dirt Bike Oil is a purpose-built synthetic motorcycle oil engineered to deliver consistent clutch engagement, superior wear protection and heat resistance in four-stroke dirt bikes that call for a 10W-50 viscosity. It is the go-to oil for KTM, Kawasaki, Yamaha, Suzuki and Husqvarna riders who want predictable power delivery from the gate drop to the checkered flag.

Four-stroke dirt bike engines share oil between the engine, transmission and wet clutch. That single sump has to handle extreme heat from high-rpm operation, heavy mechanical shear from gearbox loads, and precise friction requirements from the clutch pack. Most automotive oils and even some motorcycle oils compromise in at least one of those areas. An oil that is too slippery causes clutch slip. One that shears down under load leaves gears and bearings exposed. AMSOIL Synthetic Dirt Bike Oil was formulated from the ground up to handle all three jobs without compromise.

CONSISTENT CLUTCH FEEL FROM START TO FINISH
Clutch fade and inconsistent lever feel cost you positions. In an extreme simulated-start test, AMSOIL 10W-50 Synthetic Dirt Bike Oil delivered consistent clutch engagement through 32 simulated race starts. A leading OEM-branded oil showed inconsistent clutch-lever action and poor clutch feel after only 16 starts. When the clutch plates were inspected, the plates lubricated with AMSOIL remained clean and in good overall condition. The OEM oil plates showed visible discoloration and wear. That translates directly to confidence on holeshots and predictable modulation when picking through tight single-track on a KTM 350 SX-F or Husqvarna FC 450.

PROTECTS GEARS, BEARINGS AND PISTONS
Dirt bike transmissions take a beating. Aggressive downshifts, missed shifts and constant gear changes under heavy throttle all generate shock loads that shear oil films. AMSOIL Synthetic Dirt Bike Oil uses synthetic base oils that naturally resist viscosity loss from mechanical shear, maintaining a thick protective film between metal surfaces even under high-rpm, high-temperature operation. In Four-Ball Wear testing (ASTM D4172 at 40 kgf, 150°C, 1800 rpm, 1 hr), the 10W-50 produced a wear scar of just 0.52 mm. Premium anti-wear additives supplement that film strength to protect pistons, cam lobes, gears and crank bearings, reducing maintenance costs and extending the life of expensive internal components.

RESISTS HEAT AND VISCOSITY BREAKDOWN
Air-cooled and liquid-cooled dirt bike engines regularly see extreme oil temperatures, especially during slow technical riding or long moto sessions. AMSOIL 10W-50 Synthetic Dirt Bike Oil posts a NOACK volatility of just 4.1% weight loss (ASTM D5800), meaning it resists evaporation and thermal breakdown at sustained high temperatures. Its High-Temperature/High-Shear viscosity at 150°C measures 4.9 cP (ASTM D5481), confirming it maintains a robust protective film under the combination of extreme heat and mechanical stress that dirt bike engines generate. The result is stable viscosity and reliable protection throughout your oil change interval.

MAXIMIZES HORSEPOWER
Every bit of friction the oil generates inside the engine is energy that does not reach the rear wheel. AMSOIL Synthetic Dirt Bike Oil is formulated to reduce internal drag from the engine and transmission while still providing the friction properties the wet clutch needs to engage cleanly. That balance means more usable horsepower at the rear wheel without sacrificing clutch performance. Riders on Yamaha YZ450F, Kawasaki KX450 and Suzuki RM-Z450 machines report smoother shifting and better throttle response.

SPECIFICATIONS AND COMPATIBILITY
AMSOIL 10W-50 Synthetic Dirt Bike Oil meets JASO MA and API SG, SJ, SH, SL specifications. It is designed for dirt bikes requiring 10W-50 motorcycle oil, including models from KTM, Kawasaki, Yamaha, Suzuki and Husqvarna. This includes popular separate-sump applications like the Honda CRF platform as well as many two-stroke dirt bikes with separate engine oil requirements. The oil is compatible with other synthetic and conventional motor oils, though mixing will reduce the performance benefits and life expectancy of the AMSOIL product. Aftermarket oil additives are not recommended. AMSOIL Synthetic Dirt Bike Oil is Warranty Secure, keeping your factory warranty intact.

SERVICE LIFE
Change AMSOIL 10W-50 Synthetic Dirt Bike Oil according to the vehicle manufacturer's recommendations.