AMSOIL Metric 10W-40 Synthetic Motorcycle OilMetric Synthetic 10W-40 Motorcycle Oil is the most cost-effective upgrade you can make for any brand of motorcycle requiring a 10W-40. Fights wear, reduces friction. 



AMSOIL 10W40 Motorcycle Oil Package Sizes Include:

Quart Bottles:
Single One Quart Bottle
Case of 12 One quart bottles
Gallon Bottles:
Single One Gallon Bottle
Case of 4 One Gallon Bottles
30 Gallon Drum
55 Gallon Drum

When you see one of AMSOIL’s sponsored professional motorcycle racers participating in North America’s premiere road racing series’, keep in mind that they are using the exact Synthetic 10W-40 Motorcycle Oil that you can buy from us today. How does a professional racing-grade motorcycle oil benefit you? The powerful wear protection and friction reduction of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil will protect your investment as well as improve the power delivery and shifting performance like nothing else. Our customers offer rave reviews on this 10W-40 and if you have been wondering what all the fuss is about, give it a try. We suggest that this will be the most cost-effective upgrade you will ever make to your motorcycle.

We can offer AMSOIL Metric Synthetic 10W-40 Motorcycle Oil at the lowest prices in Canada or the US. Request a wholesale price list using the contact form on this page.

Features and Benefits of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil

  • Synthetic formula reduces friction
  • Offers powerful wear protection
  • Delivers smoother gear shifting
  • Compatible with all wet-clutches (see more on this below)
  • Protects and will not thin out in extreme heat.
  • Designed to stay in service for twice as long as other 10W-40 motorcycle oils.
  • Contains additives to prevent internal rust during storage
  • Defends against deposit, varnish and sludge formation
  • Lowers oil consumption

Professional-Grade Wear Protection

There is no greater test for a motorcycle oil than professional motorcycle racing. The engines are tuned on the very edge and heat levels and RPM are through the roof. AMSOIL Metric Synthetic 10W-40 Motorcycle Oil delivers steady protection for these engines and you can benefit this ability as well. AMSOIL starts with a shear stable 100% synthetic base oil and then loads it with anti-wear additives that will not fail in the face of extreme loads and hard gear mashing. Even if you do not push your bike to the limit, there is no better way to protect your investment for many years to come.

Protects Transmissions and Clutches

The low wear capabilities of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil also extends to transmission service. This 10W-40 is a no-compromise transmission lubricant containing tough anti-wear additives that prevent metal-to-metal wear. AMSOIL MCF 10W-40 also lengthens clutch plate life due to its ability to stabilize operating temperatures. We often get questions about whether this synthetic oil is suitable for wet-clutches and the answer is indisputably YES! It is not the “slipperiness” of synthetic oil that causes clutch plate glazing, it is friction modifiers found in car motor oil (both conventional and synthetic) that causes issues. Read more in our article Does Synthetic Motorcycle Oil Cause Wet Clutch Problems?

FZG Gear Test (ASTM D-5182)
AMSOIL Passes Gear Wear Test
FZG Gear Test (ASTM D-5182)
Torco T-4SR
Torco T-4SR Fails Motorcycle Gear Wear Test

Low Friction- High Performance

The low-friction properties of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil improves your riding experience on a number of fronts. Expect smoother, cooler operation with improved power delivery. Many touring riders also tell us about improved fuel economy. The lower friction offered by this 10W-40 motorcycle oil also results in smoother, more precise gear changes, even in extreme heat.

Protects from Rust During Long Off-Season

The protective properties of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil don’t stop when you put your bike away in the fall. AMSOIL added serious anti-rust and corrosion additives to this 10W-40 so that rust damage cannot occur in your motorcycle’s engine and transmission. In the images below, see how AMSOIL 10W-40 compares to Castrol 10W-40 Motorcycle Oil in rust testing.

Rust Test ASTM D-1748
AMSOIL MCF 10W-40 Motorcycle Oil Passes Rust Test
Rust Test ASTM D-1748
Castrol GPS 10W-40
Castrol RS R4 4T Fails Rust Test

Suitable Applications for AMSOIL Metric Synthetic 10W-40 Motorcycle Oil

  • This 10W-40 synthetic motorcycle oil by AMSOIL is suitable for 4-stroke air-cooled or liquid-cooled motorcycle, ATV, Side-By-Side or UTV engines.
  • Suitable for 2-stroke or 4-stroke transmissions requiring SAE 80W/90 or API GL-1 gear oil. Suitable for wet-clutches.
  • Recommended for motorcycle/ATV brands such as Yamaha, Suzuki, Honda, Kawasaki, BMW, KTM, Victory, Husqvarna, Arctic Cat, Can-Am Spyder, Polaris or other motorcycles where the suggested motorcycle engine oil is 10W-40.
  • Meets or exceeds the following specifications: API SG, SL/CF, CG-4; JASO MA/MA2; API GL-1; ISO-L-EMA2
  • Not recommended for applications requiring and API GL-5 or GL-4 gear oil.

Mixing AMSOIL Metric 10W-40 Synthetic Motorcycle Oil with Other Brands

AMSOIL Metric Synthetic 10W-40 Motorcycle Oil is compatible with all other brands of conventional, semi-synthetic and synthetic motorcycle engine oils. While you can safely mix AMSOIL Synthetic Oil with other brands, this will reduce the drain interval and performance capabilities of AMSOIL oil.

The use of any aftermarket oil additives is definitely NOT recommended.

Service Life for AMSOIL Metric Synthetic 10W-40 Motorcycle Oil

  • Capable of service life of up to twice the oil change interval as suggested by your owner’s manual or one full year (whichever comes first) in motorcycle engines and transmissions.
  • When using any engine oil filter other than an AMSOIL Ea Motorcycle Oil Filter, change the oil filter at the manufacturer’s recommended service interval. AMSOIL Ea Motorcycle Oil Filters are designed with the capability of staying in service for the duration of the maximum drain interval of AMSOIL Metric Synthetic 10W-40 Motorcycle Oil.
  • Off-road service: change AMSOIL Metric Synthetic 10W-40 Motorcycle Oil at the motorcycle manufacturers’ suggested service intervals.
  • Racing service or modified engines: extended oil drain service intervals are not recommended.
  • When mixing other motorcycle oil brands with AMSOIL, revert to the manufacturer’s recommended service interval.


SAE 10W-40 Metric Synthetic Motorcycle Oil (MCF)

Kinematic Viscosity @ 100°C, cSt (ASTM D-445)14.6
Kinematic Viscosity @ 40°C, cSt (ASTM D-445)91.2
Viscosity Index (ASTM D-2270)165
Fire Point °C (°F) (ASTM D-92)242 (468)
Flash Point °C (°F) (ASTM D-92)230 (446)
Pour Point °C (°F) (ASTM D-97)-43 (-45)
High Temperature/High Shear Viscosity @ 150°C , 1.0 x 106 s-1 (ASTM D 4683), cP4.7
Four Ball Wear Test (ASTM D-4172 @ 40 kgf, 150°C, 1800 rpm, 1 hour), Scar in mm0.37
Noack Volatility, % weight loss (g/100g) (ASTM D-5800)7.2
Foam (ASTM D-892, Sequence I, II & III0/20/0
Rust Test – Humidity Cabinet (ASTM D-1748)No Rust, PASS
Total Base Number11.6
AMSOIL Metric Synthetic 10W-40 Motorcycle Oil
An ideal oil for those looking to convert their motorcycles to synthetic. A safe and effective upgrade for any motorcycle requiring 10W-40.
Manufacturer: AMSOIL
Model: Metric Synthetic 10W-40 Motorcycle Oil
Product ID: MCF