20W-50 Synthetic
V-Twin Motorcycle Oil

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AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil is a premium oil designed for those who demand the absolute best lubrication for their motorcycles. It is the result of extensive research and is specially formulated to excel in all areas unique to motorcycles, including the high temperatures of air-cooled engines such as Harley-Davidson* V-twins, wet-clutch lubrication, extreme-pressure regions of gears and chains and rust common to short trips and storage. AMSOIL Synthetic V-Twin Motorcycle Oil is multi-functional and fulfills the requirements of both domestic and foreign motorcycles.

AMSOIL, the leader in 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 motorcycle.

Resists extreme heat

Retains viscosity for excellent wear protection

Convenience of one lubricant for all three sumps

Reduces Wear and Deposits

AMSOIL Synthetic V-Twin Motorcycle Oil contains a heavy treatment of anti-wear additives to reduce wear regardless of the operating conditions. It is thermally (heat) stable and contains maximum levels of oxidation inhibitor additives. After 250 hours (13,647 miles) on an engine dyno, AMSOIL Synthetic V-Twin Motorcycle Oil eliminated piston scuffing and wear for long engine life and maximum power (see image).

Withstands Extreme Heat

Big, powerful V-twin engines run extremely hot, especially in summer during stop-and-go rally or parade traffic. High heat breaks down oil formulated for standard service, inviting wear and performance-robbing deposits. AMSOIL Synthetic V-Twin Motorcycle Oil is formulated with naturally heat-resistant synthetic base oils that resist oxidation in extreme heat. Its unique additive system helps keep engines clean and running efficiently in the toughest riding conditions.

Extreme-Pressure Protection for Gears and Chains

AMSOIL Synthetic V-Twin Motorcycle Oil delivers exceptional protection in transmissions and primary chaincases. It is absolutely shear stable and will not thin out from mechanical activity. AMSOIL 20W-50 V-Twin Motorcycle Oil performs like a gear lube without the negative effects of extreme-pressure additives. In the FZG gear test, AMSOIL achieved a perfect score with a "zero" wear rating.

Delivers Superior Rust Protection

Motorcycles are prone to rust from storage, humidity and short drives. Rust can cause major damage such as roller bearing failure, wear, compression loss and blow-by. Good rust protection, however, comes by design and is not natural to motor oils. Unlike many motorcycle oils, AMSOIL Synthetic Motorcycle Oil contains special antirust agents. It passes the ASTM D1748 humidity cabinet rust test, demonstrating superior rust protection to help your engine achieve maximum performance and long life.

Provides Excellent Wet-Clutch Performance

AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil contains no friction modifiers and promotes smooth shifting and positive clutch engagement. It controls heat and helps prevent slippage and glazing, while its high TBN helps improve clutch life by resisting the acids that can degrade clutch material.

Use in motorcycles that require 15W-50 or 20W-50 motorcycle oil and any of the specifications listed below, including those made by Harley-Davidson* and Buell*.

JASO MA/MA-2 • API SG/SL/CF/CG-4 • ISO-L-EMA2

Do not use where an API GL-4 or GL-5 gear oil is required.
AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil is compatible with other synthetic and conventional motor oils. Mixing AMSOIL oils with other oils, however, will shorten the oil’s life expectancy and reduce its performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.

Aftermarket oil additives are not recommended for use with AMSOIL Synthetic Motorcycle Oils.
Recommended for use up to twice the motorcycle manufacturer change interval (miles/hours) or one year, whichever comes first, in engines, transmissions and primary chaincases. For Big Twin Harley-Davidson transmissions only, follow the Harley-Davidson recommended drain interval for synthetic oil of up to 20,000 miles or one year, whichever comes first. When using an engine filter other than AMSOIL Ea®, change the filter at standard intervals.

For off-road use, change AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil at motorcycle manufacturer-recommended intervals.

Racing or modified engines are excluded from extended drain interval recommendations. Oil changes are at the owner's discretion.
AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil is Warranty Secure, keeping your factory warranty intact. AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil is a high-performance replacement for vehicle manufacturer-branded products and is also backed by the AMSOIL Limited Warranty. For details, visit www.amsoil.com/warranty/.
AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil (MCV)
Kinematic Viscosity @ 100°C, cSt (ASTM D445) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.5
Kinematic Viscosity @ 40°C, cSt (ASTM D445) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132.8
Viscosity Index (ASTM D2270) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156
Pour Point °C (°F) (ASTM D97) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -41 (-42)
Flash Point °C (°F) (ASTM D92) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 (442)
High-Temperature/High-Shear Viscosity (ASTM D5481 @ 150°C, 1.0 X 106 s-1), cP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.6
Four-Ball Wear Test (ASTM D4172 @ 40 kgf, 150°C, 1800 rpm, 1 hr), Scar, mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.37
FZG (ASTM D5182), Load Stage Pass (Wear in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12+ (0 mm)
NOACK Volatility, % weight loss (g/100g) (ASTM D5800) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2
Foam (ASTM D892, Sequence I, II & III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0/0, 20/0, 0/0
Rust Test - Humidity Cabinet (ASTM D1748) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No Rust, Pass
Total Base Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.6

Reviews

I love Amsoil

I use it in my 2019 Indian Roadmaster

Best oil

Big motorcycle engines produce a LOT of heat, and Amsoil oil helps reduce that heat as well as standing up to the heat and provides engine protection in the most adverse conditions.

Yes I would buy this again it is the only oil I am using

I used this oil in my street glide and the engine seemed to run quieter.

Seems to be working well.

First time using Amsoil in my Road King. Trying it in all three holes as suggested. So far so good. Finding neutral much easier now. I'll let you know what it looks and feels like after the next change.

Proven quality in every thing AMSoil makes

Using it on my 2014 Slim and 2008 X bones since after their first oil change Actually use AMSoil specific lubes in all three holes Bikes run cool, quiet and shift like butter. Neutral is always there and I never see metal deposit anywhere Both bikes have similar milage and just finally got around to opening the primary on them to check chain tension and was blown away that either bike didn't. No explanation for that, sorry. Best part while in there was seeng the nylon shoe on the chain tensioner was barely worn Hope to get another 40k mi out of them Love AMSoil lubes