AMSOIL Formula 4-Stroke® 10W-40 Synthetic Scooter Oil (ASO)

Unsurpassed Protection for Scooter Engines, Transmissions and Gear Boxes

AMSOIL Formula 4-Stroke® 10W-40 Synthetic Scooter Oil (ASO) AMSOIL Formula 4-Stroke® 10W-40 Synthetic Scooter Oil (ASO) is formulated specifically to meet the special needs of today's high-tech air- and water-cooled fourstroke motorized scooters, offering unsurpassed wear protection and friction reduction for longer equipment life and cooler operating temperatures. Its exceptional shear stability ensures consistent viscosity protection and provides additional protection for transmissions and gear boxes, while its friction modifier-free formulation ensures wet clutch compatibility and smooth clutch operation. A special anti-corrosion additive package provides long-term protection during periods of inactivity and storage.

AMSOIL 100% Synthetic Scooter Oil 10W-40

AMSOIL, the leader in automotive synthetic lubrication, produced the world's first API qualified synthetic motor oil in 1972. Trust the extensive experience of AMSOIL, The First in Synthetics® , to do the best job protecting your engine.

AMSOIL Formula 4-Stroke® 10W-40 Synthetic Scooter Oil (ASO) is formulated specifically to meet the special needs of today's high-tech air- and water-cooled fourstroke motorized scooters, offering unsurpassed wear protection and friction reduction for longer equipment life and cooler operating temperatures. Its exceptional shear stability ensures consistent viscosity protection and provides additional protection for transmissions and gear boxes, while its friction modifier-free formulation ensures wet clutch compatibility and smooth clutch operation. A special anti-corrosion additive package provides long-term protection during periods of inactivity and storage.

Shear Stability

High engine rpms common to scooter applications increase shear, causing conventional lubricants to lose viscosity and reduce their ability to control wear, resulting in shorter engine life. The synthetic formulation of Formula 4-Stroke® Synthetic Scooter Oil effectively resists shear, delivering consistent viscosity protection for unsurpassed wear protection and extended equipment life.

Thermal Stability

The operating temperatures of scooter engines fluctuate greatly, especially with air-cooled engines. Formula 4-Stroke® Synthetic Scooter Oil resists breakdown at elevated temperatures, maintaining its protective viscosity for maximum wear control.

Transmission and Gear Box Compatibility

In many scooter applications, the engine and transmission and/or gear box share the same oil reservoir. Formula 4-Stroke® Synthetic Scooter Oil is absolutely shear stable and will not thin out from mechanical activity, providing superior protection for transmissions and gear boxes.

Wet Clutch Compatibility

Some scooters utilize a frictional clutch to engage and disengage the engine from the drivetrain. In many cases, this clutch is immersed in the same oil used in the engine and transmission. Formula 4-Stroke® Synthetic Scooter Oil contains no friction modifiers and is wet clutch compatible, offering smooth clutch operation and increased clutch life.

Rust and Corrosion Protection

Scooters are often subjected to extended periods of inactivity and storage, exposing the equipment to internal rust and corrosion. Formula 4-Stroke® Synthetic Scooter Oil is formulated with a special anti-corrosion additive package designed to provide long-term protection during periods of inactivity and storage.

Applications and Recommendations

AMSOIL Formula 4-Stroke® Synthetic Scooter Oil is recommended for use wherever SAE 10W-40 motor oil is specified in air- and watercooled four-stroke motorized scooter engines, transmissions and gear boxes that require the following:

  • API SG, SL/CF
  • JASO MA/MA2 (motorcycle wet clutch)

Engine manufacturers include, but are not limited to, Honda, Kawasaki, Suzuki, Yamaha, Vespa, Aprilia, Piaggio, Benelli, Vento, Kymco, Tank and TGB.

Service Life

Follow the equipment manufacturer's recommended drain intervals.

Typical Technical Properties
AMSOIL Formula 4-stroke 10W-40 Synthetic Scooter Oil (ASO)
Viscosity @ 100°C, cSt (ASTM D-445) 14.7
Viscosity @ 40°C, cSt (ASTM D-445) 94.3
Viscosity Index (ASTM D-2270) 162
Flash Point °C (°F) (COC) (ASTM D-92) 236 (457)
Fire Point °C (°F) (COC) (ASTM D-92) 250 (482)
Pour Point °C (°F) (COC) (ASTM D-97) -38 (-36)
NOACK (% weight loss) (ASTM D-5800) 5.4%
Four Ball Wear, 75°C, 1200 rpm, 40kg, 1 hour (ASTM D-4172B) 0.40
Total Base Number 7.4
HTHS (cP) 4.12

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