AMSOIL FORMULA 4-STROKE® 100% SYNTHETIC SCOOTER OIL

AMSOIL Formula 4-Stroke 10W-40 Synthetic Scooter Oil is a purpose-built 10W-40 synthetic oil designed to protect the engine, transmission, and gearbox of four-stroke scooters in a single formulation. It delivers shear stability, thermal resilience, and wet-clutch compatibility for riders who put real miles on their machines.

Modern four-stroke scooters place unusual demands on their oil. Small-displacement engines spin at high RPM, generating significant shear forces that thin out conventional oils. Air-cooled models run especially hot, accelerating oil breakdown and deposit formation. And because many scooters share a single oil sump between the engine, transmission, gearbox, and wet clutch, the oil has to do several jobs at once without compromise.

RESISTS VISCOSITY LOSS FROM HIGH-RPM SHEAR
Small scooter engines routinely operate at sustained high RPM, and that mechanical action tears apart the molecular structure of lesser oils. When viscosity drops, so does the oil film protecting critical components. AMSOIL Formula 4-Stroke Synthetic Scooter Oil maintains a kinematic viscosity of 14.7 cSt at 100°C and a high-temperature/high-shear viscosity of 4.3 cP (ASTM D5481), which means it holds its protective film strength even under the relentless shear conditions inside a Honda Grom engine or a Vespa GTS 300 powertrain. NOACK volatility is just 5.6% weight loss (ASTM D5800), confirming the oil resists evaporative thinning at elevated temperatures.

HANDLES THE HEAT OF AIR-COOLED SCOOTER ENGINES
Air-cooled scooters like the Honda Metropolitan, Yamaha Zuma, and Kymco Like 150i lack the consistent temperature regulation of liquid-cooled systems. Oil temperatures spike in stop-and-go city riding and in hot weather. Formula 4-Stroke Synthetic Scooter Oil resists thermal breakdown at these elevated temperatures, maintaining its protective viscosity and keeping deposits in check. A viscosity index of 155 (ASTM D2270) means it stays thick enough to protect when hot and flows readily when cold, with a pour point of -36°C.

WET-CLUTCH COMPATIBLE, NO FRICTION MODIFIERS
Many scooters, including popular models from Honda, Suzuki, and Yamaha, use a wet clutch immersed in the same oil that lubricates the engine and transmission. Automotive oils containing friction modifiers will cause clutch slippage in these applications. AMSOIL Formula 4-Stroke Synthetic Scooter Oil is formulated without friction modifiers and meets JASO MA/MA2 wet-clutch specifications. It promotes smooth clutch engagement and consistent shifting. It is also suitable for JASO MB applications where a lower-friction oil is required.

PROTECTS TRANSMISSIONS AND GEARBOXES IN SHARED-SUMP DESIGNS
In a shared-sump scooter like a Piaggio BV 350 or a Vespa Primavera, the same quart of oil has to lubricate gear teeth, synchronizers, and engine bearings simultaneously. An oil that shears down under gear contact leaves the transmission vulnerable. The shear-stable synthetic base oils in this formulation resist thinning from mechanical activity in the gearbox, providing consistent gear protection over the full drain interval.

GUARDS AGAINST RUST AND CORROSION DURING STORAGE
Scooters often sit for weeks or months between rides, especially in colder climates. That idle time allows moisture to accumulate inside the engine and promote rust on bearing surfaces and cylinder walls. Formula 4-Stroke Synthetic Scooter Oil includes a dedicated anti-corrosion additive package designed to protect internal components during extended periods of inactivity and seasonal storage.

Specifications and Compatibility
AMSOIL Formula 4-Stroke 10W-40 Synthetic Scooter Oil meets API SP, SN, SM, and SL specifications. It carries JASO MA/MA2 certification for wet-clutch compatibility and meets ISO-L-EMA2. It is also suitable for use in JASO MB applications. Use it in any air- or water-cooled four-stroke motorized scooter that calls for SAE 10W-40 motor oil, including models from Honda, Kawasaki, Suzuki, Yamaha, Vespa, Aprilia, Piaggio, Benelli, Vento, Kymco, Hero, Hyosung, Tank, and TGB. It is compatible with other synthetic and conventional motor oils, though mixing will reduce performance benefits and oil life.

Service Life
Follow the scooter manufacturer's recommended oil change intervals.