AMSOIL 15W-60 and 20W-40 Synthetic V-Twin Motorcycle Oil provides Indian and Victory riders the confidence and security that comes with receiving maximum protection and performance for their bikes. It presents a premium alternative to higher-priced manufacturer-branded oils.
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Product data sheets
View, download, or save a copy of the Product Data Sheet or Safety Data Sheet for AMSOIL 20W-40 100% Synthetic V-Twin Motorcycle Oil.
AMSOIL 20W-40 100% Synthetic V-Twin Motorcycle Oil (MVI) is the popular SAE 20W-40 synthetic for Victory and Indian V-twins and other motorcycles whose owner manuals call for a 20W-40 motorcycle oil. The formulation targets air-cooled V-twin heat, wet-clutch friction needs, and the gear and chain loads typical of motorcycles that share engine and transmission lubrication, in a slightly thinner top-end weight than the 20W-50 grade for moderate-climate riding and 20W-40 spec applications.
Built for air-cooled V-twin heat
Air-cooled V-twins push oil temperatures higher than liquid-cooled engines, especially in stop-and-go and parade riding. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is built on heat-resistant synthetic base oils with maximum levels of oxidation inhibitors to resist breakdown at sustained high temperatures. NOACK volatility of 2.7 percent weight loss (ASTM D5800) reflects low evaporative loss in the test, which helps maintain viscosity and reduce oil consumption on hot summer rides.
High-temperature film strength for gear and chain loads
The oil exceeds the SAE J300 minimum for high-temperature film strength to protect gears, chains, and engine components against metal-to-metal contact, with a heavy treatment of anti-wear additives that work regardless of operating conditions. High-Temperature/High-Shear viscosity (ASTM D5481 at 150 degrees C) measures 4.2 cP, comfortably above the 2.9 cP minimum that defines a 40-grade oil, supporting an oil film at the loads and temperatures that wear bearings, cams, and gear teeth in motorcycle service.
Shear-stable for transmission and gear duty
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil resists thinning from the mechanical activity inside motorcycle transmissions and gear sets. The shear-stable formulation performs like a gear lube without the negative effects of extreme-pressure additives that compromise wet-clutch friction. Kinematic viscosity at 100 degrees C of 14.0 cSt with a viscosity index of 135 supports a wide operating-temperature window without seasonal oil changes.
Wet-clutch friction control with JASO MA backing
Wet-clutch motorcycle transmissions need a JASO-rated oil rather than a passenger-car formulation that may carry modern friction modifiers. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil meets JASO MA and supports smooth shifting and positive clutch engagement, with a total base number of 11.6 to help neutralize acids that can degrade clutch material over the service interval. The formula also meets API SM and ILSAC GF-4.
Catalytic-converter compatibility and rust protection
The formula meets the requirements for emission-system protection and is designed for use in motorcycles equipped with catalytic converters. Rust protection comes by design rather than as a byproduct of standard motor oil chemistry. Specific anti-rust agents in AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil guard against the storage humidity and short-trip moisture that drive uncontrolled wear, compression loss, and blow-by in motorcycles parked through the off-season or used for short rides that never bring oil temperature high enough to boil off water.
Recommended applications and service intervals
Use AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil in motorcycles that require a 20W-40 motorcycle oil and any of the listed specifications, including Victory and Indian models and other motorcycles that share these requirements. Specifications met include JASO MA, API SM, and ILSAC GF-4. Confirm viscosity, specification, and application by bike with the AMSOIL vehicle lookup guide before placing an order.
On-road engines and transmissions, paired with an AMSOIL Motorcycle Oil Filter: up to 2X the motorcycle manufacturer-recommended change interval or one year, whichever comes first.
On-road service with a non-AMSOIL oil filter: change the oil at the standard motorcycle manufacturer-recommended interval.
Off-road use in engines and transmissions: change at the standard motorcycle manufacturer-recommended change interval.
Racing or engines modified from the original factory design: no extended-drain recommendation is made; oil changes are at the owner's discretion.
The oil is compatible with other synthetic and conventional motor oils, but mixing shortens service life and reduces performance benefits, so extended drain intervals are not supported on mixed oil. Aftermarket oil additives are not recommended for use with AMSOIL Synthetic V-Twin Motorcycle Oil. For Victory and Indian fit guidance, JASO context, and a comparison against the 20W-50 V-twin grade, review the AMSOIL motorcycle oil guide.
Typical technical properties
Property
Value
Kinematic Viscosity at 100 degrees C, cSt (ASTM D445)
14.0
Kinematic Viscosity at 40 degrees C, cSt (ASTM D445)
105
Viscosity Index (ASTM D2270)
135
Flash Point, degrees C (degrees F) (ASTM D92)
232 (450)
Fire Point, degrees C (degrees F) (ASTM D92)
258 (496)
Pour Point, degrees C (degrees F) (ASTM D97)
-41 (-42)
High-Temperature/High-Shear Viscosity at 150 degrees C, cP (ASTM D5481)
4.2
Four-Ball Wear Test, Scar Diameter, mm (ASTM D4172)
0.41
NOACK Volatility, percent weight loss (ASTM D5800)
2.7
Foam Test, Sequence I/II/III (ASTM D892)
0/10/0
Total Base Number
11.6
Order AMSOIL 20W-40 100% Synthetic V-Twin Motorcycle Oil
AMSOIL 20W-40 100% Synthetic V-Twin Motorcycle Oil ships in the quart bottle (MVIQT-EA), case of 12 quarts (MVIQT-CA), and 55 gallon drum (MVI55-EA). The product is Warranty Secure, meaning the formula is a high-performance replacement for vehicle-manufacturer-branded products and is also backed by the AMSOIL Limited Warranty when used as directed. For fit by bike, review the AMSOIL vehicle lookup guide and the AMSOIL motorcycle oil guide before placing an order. Order Now.
A 20W-40 motorcycle oil is specified for V-twin and other motorcycles whose owner manual calls for the 20W-40 viscosity grade. AMSOIL 20W-40 100% Synthetic V-Twin Motorcycle Oil is developed for Victory and Indian motorcycles requiring a 20W-40 oil and meets JASO MA, API SM, and ILSAC GF-4 for engine and wet-clutch transmission service.
What is the difference between 20W-40 and 20W-50 V-Twin oil?
Both grades share the 20W cold-rating and are formulated for V-twin engines and wet-clutch transmissions. The 20W-50 grade (MCV) is the heavier 50-weight option for the largest air-cooled big twins and warmer-climate riding. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil (MVI) is the lighter 40-weight option for motorcycles whose manual specifies a 20W-40 grade, including Victory and Indian models that call for that viscosity.
Is 20W-40 V-Twin Motorcycle Oil approved for Indian and Victory motorcycles?
The product is developed for use in Victory and Indian motorcycles that call for a 20W-40 motorcycle oil, and it is Warranty Secure when used as directed. Warranty Secure means the formula is a high-performance replacement for vehicle-manufacturer-branded products and is also backed by the AMSOIL Limited Warranty. Indian and Victory are not affiliated with AMSOIL.
Is the oil JASO MA wet-clutch compatible?
Yes. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil meets JASO MA for wet-clutch friction performance, supporting smooth shifting and positive clutch engagement in motorcycles that share engine, transmission, and clutch lubrication. The formula also meets API SM and ILSAC GF-4, and a total base number of 11.6 helps neutralize acids that can degrade clutch material over the service interval.
How long can the oil go between changes?
For on-road engines and transmissions paired with an AMSOIL Motorcycle Oil Filter, the formula is capable of providing premium protection for up to 2X the motorcycle manufacturer-recommended change interval or one year, whichever comes first. With other-brand oil filters, change at the standard interval. Off-road riding follows the motorcycle manufacturer's standard interval, and racing or modified engines are excluded from extended drains.
Can it be mixed with conventional or other synthetic motorcycle oils?
The oil is compatible with other synthetic and conventional motor oils, but mixing shortens service life and reduces performance benefits. Extended drain intervals are not supported when AMSOIL Synthetic V-Twin Motorcycle Oil has been mixed with another product. Aftermarket oil additives are not recommended for use with AMSOIL Synthetic V-Twin Motorcycle Oil.
Is the formula safe for catalytic-converter motorcycles?
Yes. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil meets the requirements for emission-system protection and is designed for use in motorcycles equipped with catalytic converters. The formula also contains specific anti-rust agents that protect against rust and corrosion during storage and short-trip riding.
