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

Outstanding Protection for Scooter Engines, Transmissions and Gearboxes. Meets the needs of today's high-tech air and water-cooled four-stroke motorized scooters. Unsurpassed wear protection and friction reduction for longer equipment life. Protects transmissions and gear boxes. Wet-clutch compatible to insure smooth clutch operation. Provides long-term protection during storage.

Package sizes include:

Quart Bottle
Quart Bottles (case of 12)

Product Code: ASO • Brand: AMSOIL




MSDS Data Sheet

Product Details Tech Data Reviews & RatingRelated Videos

Product Applications
AMSOIL Formula 4-Stroke Synthetic Scooter Oil is recommended for use wherever SAE 10W-40 motor oil is specified in air and water-cooled four-stroke motorized scooter engines, transmissions and gearboxes that require the following:

Product Application Specs

• API SG, SL/CF
• JASO MA/MA2 (motorcycle wet clutch)
• ISO-L-EMA2

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.

Product Description
AMSOIL Formula 4-Stroke 10W-40 Synthetic Scooter Oil is formulated specifically to meet the special needs of today’s high-tech air and water-cooled four-stroke motorized scooters, offering outstanding wear protection and friction reduction for longer equipment life and cooler operating temperatures. Its exceptional shear stability provides consistent viscosity protection and additional protection for transmissions and gearboxes, 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 rpm common to scooter applications increases 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 outstanding 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.

Service Life
Follow the equipment manufacturer's recommended drain intervals.

Mixing AMSOIL
AMSOIL Formula 4-Stroke Synthetic Scooter Oil is compatible with conventional and synthetic motor oils. Mixing AMSOIL motor oils with other oils, however, will shorten the oil life expectancy and reduce the performance benefits. Aftermarket oil additives are not recommended for use with AMSOIL motor oils.

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS).

Click here to view the MSDS Data Sheet for AMSOIL ASO.

Keep out of the reach of children. Don't pollute. Return used oil to collection centers.

TYPICAL TECHNICAL PROPERTIES
  Formula 4-Stroke® 10W-40 Synthetic Scooter Oil (ASO)
Kinematic Viscosity @ 100°C, cSt (ASTM D-445)14.8
Kinematic Viscosity @ 40°C, cSt (ASTM D-445)98.9
Viscosity Index (ASTM D-2270)156
Pour Point °C (°F) (ASTM D-97)-38 (-36)
Flash Point °C (°F) (ASTM D-92)230 (446)
Fire Point °C (°F) (ASTM D-92)250 (482)
Four Ball Wear Test
(ASTM D-4172B: 40 kgf, 75°C, 1200 rpm, 1 hr), Scar, mm		0.40
Noack Volatility, % weight loss (g/100g) (ASTM D-5800) 5.8
High Temperature/High Shear Viscosity
(ASTM D-4683 @ 150°C, 1.0 X 106 s.-1), cP		4.1
Total Base Number7.4

Tips to Effectively Winterize Gasoline Powered Vehicles & Equipment

Also use AMSOIL Gasoline Stabilizer, in addition to fresh Oil & Filter

Did this product meet your expectations?

(click on a star to rate)
Product Name: Small Engine Motor Oils (ASO,ASE)
Current Rating: 4.85 out of 5 stars
Total Votes: 10 vote(s)

Reviewed by Ivan: space

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

Hi, I am Ivan from Indonesia
Amsoil 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO) For scooter engine capacity up to how many cc?. Can it be used for the first generation Yamaha Aerox VVA 155cc scooter engine capacity?

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)
Discussion Url

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

Yes, you can use. Just make sure the recommended oil specification include any one of these: API SG, SL/CF, JASO MA/MA2, ISO-L-EMA2 Replied by Tech Admin

Reviewed by Shaun : space

Best scooter oil

I have been using this in my 06 Yamaha Vino 125 Cold starting no problem no rough idling everything runs smooth been using it for one year engine temperature for air cooled motor has been extremely improved compared to mobile one Castro royal purple you know the cheap stuff

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)
Discussion Url

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by johnny: space

amazing stuff cleans last longer runs smoother better mpg

amazing

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Rickiboy: space

Best oil

Very good quality

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by The repair guy: space

Been using for 5 years

I use this oil in my Yamaha majesty 400 amd my Kymco Xciting 500ri. Change it every spring. Never any problems,smooth running engine,no noise,no leaking! You have an exellent product!

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Larry: space

Very good oil

My wife talked me into buying 2 scooters to putt around the countryside. They are only 49cc engines but since I changed the oil to synthetic they picked up a few miles per hour. I believe synthetic oils are great for any moving metal parts. No wear, No friction, saves money in years to come and makes my engines very dependable.

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Jean-Michel: space

Amsoil oils review

I have used Amsoil oils for the last 15years on all my toys. Never had a problem. These oils are prime quality at a reasonable price.
You can't go wrong using them!

Item Reviewed: 10W-40 Formula 4 Stroke® Synthetic Scooter Oil (ASO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Kenwood: space

The only oil for my mower!

I bought a new riding mower and wanted the best oil I could find for it. I found the Formula 4 Stroke small engine oil and liked the fact that it was specifically designed for small engines. This year has been very hot and the grass has grown like crazy so the Amsoil has been put to the test and passed with flying colors. This is the only oil I will put in my mowers from now on.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by W: space

No turning back!! Love this oil!!

My mower runs cooler/ quieter and since this oil I don't ever have to add oil between cuts. It's worth Every penny!!

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Jack: space

Excellent

Generator

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by PB: space

Quality alternative/peace of mind

I use the formula 4 stroke in all my small engine equipment: pressure washer, lawn mower, engine-driven air compressor, brush mower. I feel it's a quality alternative to brands at local parts stores and it gives me peace-of-mind for longer oil change intervals and severe duty service-just as intended.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Shakey: space

I would buy this product again

I bought a new Exmark 24hp Kawasaki engine got 300 hr on it already change it ever 50hr so far not been a hair below full at 50hr yet 👍🏼

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by WD: space

Best warm weather oil for outdoor power equipment

We use Formula 4-Stroke in our commercial lawn mowing business...45 deg F to 100 deg F. It is proving a great oil, no consumption, engines still running like new, and the oil still looks fresh at the OCI. At the 10w rating, it will be fine for cool weather mowing. I'd use the 0w40 formula for severe winter OPE use.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Big guy: space

Great product keep Small Engines running clean

Using on small engines generators lawnmowers and snow blowers

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Northeast Homeowner: space

Great small engine oil

I use this oil in my 36 inch walk behind mower, the snow blower and a permanent outdoor standby generator. These small engines are still full on the dipstick at their annual oil changes and the oil looks clean. All of this power equipment is now 10 years old and they are still going strong. Thanks for making such a great product for small engines.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Leonard: space

I have purchased several times

Typical high quality Amsoil product. I use it in my 3 mowers.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by None: space

The oil is second to no other brand.

I use a soil in all my lawn and garden Equiptment , very happy with it ,without a doubt the best oil there is,

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Steve in Tennessee: space

Excellent protection, as you would expect!

I use this oil in my walk behind mower & lawn tractor. One change through the season with about 50 hours on the work horse lawn tractor & the oil is still still clean, I almost feel wasteful when I change it.
However, I know better. I've used Amsoil for the last 12 years & have not been disappointed.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Brian: space

repeat buyer of this oil

I use this oil in riding and push mower with no problems and know its of the same quality as the automotive oil. I've found Amsoil to be a very reliable especially when I lived in the midwest and will continue to run Amsoil is all my vehicles. I give two thumbs up to the Z-Rod oil as well my '62 Galaxie sure likes this oil.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by JCD: space

Best small engine oil

Has treated me well in all 4stroke small engine equipment for over a decade. Have a 10+ year old power washer, generator, and lawn mower that are still running as good as new.

Item Reviewed: Small Engine Motor Oils (ASO,ASE)
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