Motorcycle Oil & Filters

Amsoil Motorcycle Oil Products
Amsoil Motorcycle Oil Products
Amsoil Motorcycle Oil Products
Amsoil Motorcycle Oil Products

What's a motorcyclist to believe? On one hand, cyclists are told by equipment manufacturers that automotive motor oils are not capable of protecting their bikes. On the other hand, Amsoil synthetic motor oils have offered unparalleled protection and performance to motorcycles for 25 years.

Amsoil synthetic 10W-40 and 20W-50 motor oils have always given motorcyclists what they need: superior wear protection for high-stress motorcycle engines and transmissions and clutches that stay clean and deposit fee.


Amsoil 20W-50 synthetic motorcycle oil is recommended for Harley-Davidson, Buell, KTM, Ducati, Aprila, BMW, Triumph, and other motorcycle engines. Superior synthetic formulation provides long service life and maximum protection against engine wear. Superior shear stability provides unsurpassed protection for high performance engines, transmissions, and primary chaincases. No friction modifiers. Wet clutch compatible.

Amsoil 10W-40 synthetic motorcycle oil is recommended for Honda, Yamaha, Kawasaki, Victory, BMW, and other motorcycle engines. Superior synthetic formulation provides long service life and maximum protection against engine wear. Superior shear stability provides unsurpassed protection for high performance engines and transmissions. No friction modifiers. Wet clutch compatible.

-Amsoil Motorcycle oil is recommended for all V-twin and other motorcycle eingines requiring an API CD, SG-CG, or SH-CD oil.

-It is wet clutch comatible.

-Superior 12+ TBN synthetic formulation provides long service life and maximum protection against engine wear.

-Runs cooler-reduces crankcase temperature.

Use Amsoil for the Best Protection Possible in Your Motorcycle!

AMS Orange County Choppers

Steve Scheuring, team owner of the AMSOIL/Scheuring
Race Team with Orange County Choppers

Reduce Friction, Heat and Wear
In high heat conditions, engine protection is not sacrificed with AMSOIL Synthetic Motorcycle Oils. They have the best high temperature film strength of all oils tested.

10W-40 Motorcycle Oil
High Temperature Viscosity Protection
Higher values reflect better film strength
ASTM Test Method D-4683 March 16, 2005

20W-50 Motorcycle Oil
High Temperature Viscosity Protection
Higher values reflect better film strength
ASTM Test Method D-4683 March 16, 2005

10W-40 Motorcycle Oil High Temperature Viscosity Protection 20W-50 Motorcycle Oil High Temperature Viscosity Protection

They also contain a heavy treatment of anti-wear additives to reduce wear regardless of the operating conditions.

10W-40 Motorcycle Oil
Wear Comparison
ASTM Test Method D-4172 March 16, 2005

20W-50 Motorcycle Oil
Wear Comparison
ASTM Test Method D-4172 March 16, 2005

10W-40 Motorcycle Oil Wear Comparison High Temperature Viscosity Protection Wear Comparison

Provide Extreme Pressure Quality Protection for Gears and Chains

With Amsoil Synthetic Motorcycle Oils, there is no need for separate transmission or primary chaincase lubricants. It is absolutely shear stable and will not thin out from mechanical activity. AMSOAmsoil IL MCF and MCV perform like a gear lube without the negative effects of extreme pressure additives. In the FZG gear test (ASTM D-5182), both Amsoil MCF and MCV achieved a perfect score with a "ZERO" wear rating. See these test results:

FZG Gear Test (ASTM D-5182)
FZG Gear Test (ASTM D-5182)
FZG Gear Test (ASTM D-5182) FZG Gear Test (ASTM D-5182)
FZG Gear Test (ASTM D-5182)
Motul 300 V 10W-40
FZG Gear Test (ASTM D-5182)
Motul 300V 15W-50
FZG Gear Test (ASTM D-5182) FZG Gear Test (ASTM D-5182)

Deliver Superior Rust Protection
Motorcycles are prone to rust from storage, humidity and short drives. Rust can cause major damage such as roller bearing failure, uncontrolled wear, compression loss and blow-by. Good rust protection comes by design and is not natural to engine oils. Unlike many motorcycle oils, Amsoil MCF and MCV contain special anti-rust agents. They pass the ASTM D-1748 Humidity Cabinet Rust Test and clearly demonstrate superior rust protection. See for yourself:

Rust Test ASTM D-1748
Rust Test ASTM D-1748
Rust Test AMSOIL 10W-40 Rust Test AMSOIL 20W-50
Rust Test ASTM D-1748
Castrol GPS 10W-40
Rust Test ASTM D-1748
Castrol GPS 20W-50
Rust Test Castrol GPS 10W-40 Rust Test Castrol GPS 20W-50

Provide Excellent Wet Clutch Performance
Amsoil MCF and MCV contain no friction modifiers and promote smooth shifting and positive clutch engagement. AMSOIL MCF and MCV control heat and prevent slippage and glazing, and its high TBN (total base number) resist acids that can degrade clutch material, thereby helping improve clutch life.

Amsoil Synthetic Motorcycle Oils

  • Excellent for roller bearings and do not cause "skate" or "float in V-Twin Engines
  • Prevent foaming in high-RPM engines
  • Eliminate the need for multiple lubricants
  • Absolute shear stability maintains protective viscosity in high heat, high shear conditions
  • Better performance and price than competitive motorcycle oils
  • Recommended for twice the manufacturer's recommended drain interval for on-road motorcycles
  • &Provide exceptional protection against rust and corrosion during storage
  • Robust anti-wear additive packages provide superior wear protection and longer equipment life

Don't forget the oil filter!

Don't forget the oil filter!

Amsoil also makes oil filters for motorcyles. Own a Harley? Amsoil also makes chrome oil filters. Amsoil EA motorcyle oil filters feature full synthetic nanofiber technology, providing superior protection for motorcyles, ATV's, and four stroke personal watercraft, snowmobiles and outboard motors. EA motorcycle oil filters last longer, stop smaller dirt particles and offer less restriction, extending equipment and filter life and improving performance. EA motorcyle oil filters are fluted for easy removal from motorcyles. Avalible in black and chrome.


Ea Motorcycle Oil Filters feature a specially constructed silicone anti-drainback valve and a nitrile sealing gasket to go along with the full-synthetic Ea nanofiber media. The anti-drainback valve provides excellent protection during startup and remains flexible in all temperatures, and the nitrile sealing gasket resists chemical breakdown, providing excellent durability and ensuring long filter life.


The unique construction and full-synthetic media of Amsoil Ea Motorcycle Oil Filters allow them to provide unmatched performance in motorcycles and other power sports equipment. EaOM Filters last longer, stop smaller dirt particles and offer less restriction than other filters. Ea Motorcycle Oil Filters provide filtering efficiency of 98.7 percent at 15 microns, outperforming the best cellulose/synthetic blend media on the market. For maximum protection, Amsoil recommends changing Ea Motorcycle Oil Filters at every oil change.


Amsoil Ea Motorcycle Oil Filters provide unsurpassed protection for motorcycles, ATVs, four-stroke personal watercraft, four-stroke snowmobiles and four-stroke outboards. Amsoil currently provides 16 Ea Motorcycle Oil Filters manufactured for the most popular power sports applications, eight of which are chrome plated.


Amsoil Ea Motorcycle Air FiltersEAAM Group

The filtration media in the Ea Motorcycle Air Filter is pleated and has epoxy-coated wire on the face and back of the media for additional strength and stiffness. High quality plastisol potting compounds bond the pleat packs to the plastic or aluminum side plates. The S&S style round filters are manufactured with high-quality plastisol that bonds the media to the wire backing and sealing area.


The synthetic nanofiber media featured in Amsoil Ea Motorcycle Air Filters have sub-micron diameters and small inter-fiber spaces, resulting in more contaminants being captured on the surface of the media and lower restriction. Cellulose, wetted gauze and foam filters are larger and have larger spaces between the media that cause contaminants to load in the depth of the filter, resulting in airflow path plugging, higher restriction and lower capacity.


Amsoil Ea Motorcycle Air Filters are cleanable, providing unsurpassed protection and long service life. Amsoil Ea Motorcycle Air Filters should be cleaned every year or according to operating conditions. Operation in extremely dusty or dirty environments may require more frequent cleaning. Ea Motorcycle Air Filters should be changed every four years.


Amsoil Ea Motorcycle Air Filters are cleaned in the same manner as Amsoil Ea Air Filters for cars and light trucks: with a vacuum or shop air.

To clean with a vacuum, place the filter on a flat surface and carefully vacuum the filter media on the dirty side where the incoming airflow enters the filter. Using a vacuum with too much suction may damage the filter.

To clean with shop air, hold the filter with one hand and carefully blow the filter media at a 45-degree angle on the clean side of the filter using low-pressure (15 to 20 psi) shop air. Using too much air pressure will damage the filter media.

EaAM24 Motorcycle Air Filter

The new EaAM24 Motorcycle Air Filter bridges the gap from American Iron to Metric V-twin cruisers and is designed to fit on Baron Big Air™ aftermarket induction systems. The EaAM24 replaces the K&N E-3333.

Amsoil EaAM24 Motorcycle Air Filter

Amsoil currently provides eight Ea Motorcycle Air Filters manufactured for the most popular Harley Davidson models from the years 1988 to 2006, including motorcycles equipped with S&S carburetors and air cleaner housings.

What About Storage?

Amsoil Fogging Oil and Gasoline Stabilizer

Engine Fogging Oil

Two- and four-stroke motorcycles are commonly operated seasonally or infrequently, then stored for long periods of time. During these periods of inactivity, and as a result of fluctuations in ambient temperatures, water vapor can form condensate within the engine, eventually becoming surface corrosion on cylinder liners, piston rings, anti-friction bearings and steel/iron contact surfaces on rotational seals.

Amsoil Engine Fogging Oil offers superior film retention, providing long-term protection against corrosion and dry starts, extending engine life and reducing operating expenses. Its aerosol spray formulation offers easy and clean applications, while reaching more components and offering better distribution than straight motor oil.

Amsoil Engine Fogging Oil applications include, but are not limited to, motorcycles, snowmobiles, ATVs, outboard motors, stern drive and inboard marine engines, personal watercraft, lawn equipment, cars, trucks and much more.


Gasoline StabilizerIt is difficult to drain all of the fuel from equipment before storage, and doing so would expose the system to other problems, including the formation of rust and corrosion on the bare metal in the tank and fuel system and the drying and cracking of gaskets and seals. Some fuels are pre-treated with oxidation inhibitors that allow them to be stored for short periods without forming excessive deposits, while other fuels have no inhibitors at all.

Amsoil Gasoline Stabilizer reduces the oxidation process that occurs when fuel is stored for extended periods. It prevents the formation of varnish and sludge which can clog injectors, stick floats and cause poor engine performance. Amsoil Gasoline Stabilizer is ideal for stored seasonal equipment such as motorcycles, snowmobiles, lawnmowers and boats. The treat rate is one ounce with every 2.5 gallons of fuel. One bottle treats 40 gallons.

What other Amsoil products can I use in my motorcycle?

Shock Therapy Suspension Fluid Bottle

Formulated for fade-free dampening and smooth rebounds in racing and recreational applications. Controls friction and heat, reduces wear, scuffing, frictional energy loss and heat buildup and prevents fade more effectively than conventional suspension fluids. Ideal for both front forks and shocks. Available in two viscosity grades.

MP Metal Protector Spray Can


Disperses water and protects metal surfaces from rust and corrosion. Penetrates existing rust buildup and dries wet electrical systems.

P.I. Performance Improver Bottle

Dissolves and removes fuel system deposits and other contaminants for improved power and overall performance in gasoline engines. Reduces exhaust emissions. Improves engine idle, response and starting. Ideal for both fuel injected and carbureted systems. Twelve ounces treats20 gallons of gas.

Heavy-Duty Metal Protector


A heavy-duty spray lubricant fortified with special rust and corrosion inhibitors. It penetrates and adheres to metal surfaces, leaving a long-lasting protective coating. Ideal for motorcycle, bicycle and ATV chains.

Amsoil Series 2000 Racing Grease Cartridge

Ultimate protection for hard-driven, high performance motorcycles. Dramatically reduces friction and wear for improved performance .


Wear Test Comparison - Amsoil vs. Harley Screamin' Eagle

 The recent introduction of Screamin' Eagle® Synthetic Lubricant by Harley-Davidson® indicates the Motor Company has finally recognized the benefits of running synthetic motorcycle oil in their air-cooled engines.The recent introduction of Screamin' Eagle® Synthetic Lubricant by Harley-Davidson® indicates the Motor Company has finally recognized the benefits of running synthetic motorcycle oil in their air-cooled engines. After years of advising dealers and customers to avoid using synthetic oils in their bikes, it's natural to wonder why the company is suddenly marketing one.

For the past 20 years, Harley-Davidson ® has claimed its petroleum-based Genuine H-D Oil is best for the "unique requirements of Harley-Davidson® air-cooled V-twin engines." However, laboratory testing has consistently revealed that Genuine H-D Oil does not provide the best protection possible for Harley-Davidson® engines. In fact, Four-Ball Wear Tests show Harley-Davidson® 20W-50 Motorcycle Oil leaves a wear scar nearly 80 percent larger than that left by Amsoil Synthetic 20W-50 Motorcycle Oil.

Amsoil versus Screamin' Eagle Four-Ball Wear test Graph

Four-Ball Wear Test (ASTM D4172), 40kg pressure @ 150 degrees C, 1800 rpm for 1 hour duration
April 2003 test results

The Four-Ball Wear Test is the industry's standard test method for measuring the wear preventive characteristics of a lubricant. Placed in a bath of the test lubricant, three fixed steel balls are put into contact with a fourth ball in rotating contact at preset test conditions. Lubricant wear protection properties are measured by comparing the average wear scars on the three fixed balls. The smaller the average wear scar, the better the protection.

One of the major benefits of running a synthetic motorcycle oil is its resistance to oxidation and thermal degradation, which inhibit the formation of sludge and deposits that contribute to increased wear. In the past, Harley-Davidson® has defended use of its Genuine H-D Oil by arguing that oil breakdown in extreme heat is a non-issue because extreme heat conditions are not normally faced by motorcycle engines, while the superior cold-temperature benefits of synthetics also don't apply to Harleys.

The fact is, engine oil in Harley-Davidson® motorcycles is subject to very high temperatures. Being air-cooled, Harley-Davidson® engines get especially hot while idling in traffic, commonly reaching temperatures up to 240 degrees Fahrenheit. As heat and oxidation increase, so does viscosity, adversely affecting the lubricating qualities of the oil and increasing wear.

The water, soot and acid byproducts of combustion also contribute to deposit formation. Harley-Davidson® has stressed the importance of regular oil changes in order to remove these contaminants. Of course, promoting regular oil changes is also a good way to promote using petroleum-based Genuine H-D Oil. High-quality synthetic oils formulated with high-performance additives effectively withstand such contaminants, allowing motorcyclists to safely extend drain intervals.

In support of their about-face and the introduction of a synthetic oil, Harley maintains that "the Motor Company has never supported the use of synthetic products in our vehicles because there has never been any test validations completed on the numerous formulations in HD/Buell motorcycles. This product has been exclusively designed for Harley-Davidson® and is the only synthetic product TESTED and CERTIFIED by Harley-Davidson® engineering for use in HD/Buell motorcycles."

Although this is necessary marketing hype, Harley-Davidson® V-twin air-cooled engines are not unique in their lubrication requirements and do not require a special Harley-only fluid. There is nothing about Screamin' Eagle® Synthetic Motorcycle Oil that sets it apart from, or makes it better than, many other synthetic motorcycle oil formulations, except that Harley-Davidson® is marketing it and directly profiting from the sales.

According to Harley-Davidson®, one of the unique benefits offered by Screamin' Eagle® Synthetic Motorcycle Oil is its versatility. For the first time the company is recommending an oil that can be used in the engines, primary chaincases and transmissions of most Harley-Davidson® motorcycles, including Evolution XL, Evolution 1340, Twin Cam 88 and 88B, Revolution and Buell models. This feature, however, is not unique. AMSOIL 20W-50 Synthetic Motorcycle Oil may also be used in the engines, primary chaincases and transmissions of these applications, providing superior lubricating protection in each component.

How does Screamin' Eagle® Synthetic Motorcycle Oil measure up to Amsoil in wear protection? Four-Ball Wear Test results indicate that Amsoil Synthetic Motorcycle Oil still provides the best protection possible for motorcycles. In fact, Screamin' Eagle® Synthetic Motorcycle Oil leaves a wear scar nearly 80 percent larger than Amsoil 20W-50 Synthetic Motorcycle Oil.

Not only does Amsoil Synthetic Motorcycle Oil offer greater wear protection than Screamin' Eagle® Synthetic Motorcycle Oil, it also delivers greater value. Suggested retail price of Screamin' Eagle® is nearly $2 a quart higher than AMSOIL 20W-50 Motorcycle Oil. And because Amsoil Synthetic Motorcycle Oil may be used for extended drain intervals of up to twice the manufacturer's suggested interval, while Screamin' Eagle® is recommended for standard drain intervals, Amsoil customers realize additional savings.

Harley-Davidson® claims Screamin' Eagle® Synthetic Motorcycle Oil has been "exclusively designed" for use in their motorcycles, pointing to extensive bench testing and over 230,000 miles of durability testing to back it up. Amsoil Inc. has 30 years of experience providing superior lubricating protection for all brands of motorcycles, and Amsoil Synthetic Motorcycle Oils have been tested in millions of over-the-road miles. Testimonials from countless motorcyclists further demonstrate the superiority of Amsoil Synthetic Motorcycle Oils.

Formulated with top-of-the-line synthetic base stocks and high-temperature deposit control additives, Amsoil Synthetic Motorcycle Oils provide superior protection and performance for motorcycles in all operating conditions. Amsoil Motorcycle Oils effectively withstand oxidation and thermal degradation, keep wear to an absolute minimum, hold contaminants in suspension and keep engines running cool and clean .

Amsoil Synthetic Motorcycle Oils

  • Reduce operating temperatures
  • Keep engines clean and deposit-free
  • Provide maximum protection against wear
  • Formulated without friction modifiers for smooth performance
  • Saves money with extended drain intervals of up to two times the manufacturers' recommendations

American Iron MagazineThe Great Oil Debate: Amsoil

The manufacturer of the first API-rated synthetic motor oil offers its experience and insights

By Ed Newman, Amsoil Marketing and Advertising Manager

Appeared in the February 2001 Issue of American Iron Magazine

This article was written in late 2000, before Harley-Davidson accepted the fact that synthetic oils were better for their bikes, and long before Harley came out with their own Screaming Eagle line. Since that time, Amsoil has introduced two new premium motorcycle oil formulations with GL-1 ratings, as well as a line of Absolute Efficiency Motorcycle Oil Filters that no longer require changing in the middle of an extended drain interval.


The cover of the most recent Forbes ASAP exclaims in large red letters, "What Is True?" The magazine chooses a theme for each issue and in an age of information, misinformation and disinformation, it comes as no small surprise that people are confused about almost everything. Contradictions and competing viewpoints abound. No question about it, it's not easy being a consumer sometimes.

Nowhere is this more of a problem than in the area of motorcycle lubrication. On the one hand bikers are told by equipment manufacturers that automobile oils are not capable of protecting their bikes. On the other hand, a synthetic motor oil company like Amsoil has been providing motorcycles with superb performance and protection for nearly three decades. What's a motorcyclist to believe?

This spring Donny Petersen defended, even recommended, the use of synthetic motor oils. In November Harley-Davidson responded, taking Donny to task and challenging many of his assertions. A rebuttal by Chuck Goldmann (ExxonMobil) provided readers with an excellent overview of synthetic motor oils and their advantages over petroleum.

I'd like to commend American Iron for creating this opportunity for the exchange of ideas regarding the care and feeding of our machines, and to Donny's courage in putting his convictions down in black and white as a starting point. It's always easier to say nothing than to go on record and get fired at from every angle. The likelihood of getting shot is significantly reduced when you avoid the front lines.

This article is a response to all three of the abovementioned articles. Amsoil synthetic motor oils were the first API rated synthetic motor oils in the world when introduced in 1972. With nearly three decades of experience, and documentation, Amsoil can make a contribution to this "Great Oil Debate." Our tech services staff has been answering questions by concerned Harley riders for ages anyways. We might as well attempt to present publicly what we have been saying all along.

My premise is this: Everyone knows synthetic oil is better than refined petroleum. Why not use it?


Older Amsoil Synthetic Motorcycle Oil BottleThe advantages of synthetic motor oils are well known and have been written about for decades. I have SAE (Society of Automotive Engineers, Inc.) papers in my files that repeatedly endorsed the various benefits of synthetics. Whether extended service life, improved fuel economy, increased power, reduced friction and wear, resistance to breakdown, better low and high temperature protection, you name it, the documentation is out there. The studies have been done.

All of this leads one to ask a couple fundamental questions. Is the Harley V-Twin engine different from all other engines in the world? Is there something so unique with a Harley engine that all of the lubrication rules that apply to all other four stroke engines must be thrown out the window?

Yes, theirs is air-cooled and can run hot. For this reason alone one would think it even more important to have a premium synthetic motor oil.

One of Donny's comments that bears repeating came near the conclusion of his April column. "The Motor Company didn't reinvent the air-cooled engine and, therefore, its engines don't require specially formulated, Harley-only fluids." This summary remark stands at the crux of the debate.


There were two topics which the previous writers waded into with great detail which I would like to re-visit briefly here: dual qualified motor oils and additive chemistry.

Historically, one of the biggest problems Amsoil has faced when selling motor oils to the motorcycle market has to do with this notion that automobile oils can't be used in motorcycles. Chuck Goldmann did an excellent job of explaining how some motor oils might not be suited for both applications, but that some motor oils most certainly are. (I won't fault him for mentioning that he personally uses a Mobil product. As you would expect, we use Amsoil products, which Chuck knows are very good.)

There are actually two issues here. The first is that the motor oil be capable of meeting both passenger car and diesel performance requirements. The second issue has to do with the use of friction modifiers. The truth is that friction modifiers have never been a real performance issue. OEMs (bike manufacturers), however, created such a strong public perception against them that in 1998 Amsoil re-formulated its two leading oils for the motorcycle market. Later, because of the continued misinformation that an automobile oil cannot be used as a motorcycle oil, Amsoil took the last step of producing two grades of Amsoil synthetic motorcycle oil.

Public perceptions and fears can drive consumer behavior, whether true or not. Last year's Millennial Day Meltdown fear resulted in tremendous sales of generators and packaged dried foods. The fear driving this debate revolves around the question of whether it is acceptable or safe to use anything but Factory oil.


Chemistry Class All of the articles presented chemistry lessons. I'm not sure how important many of these details are for riders, but it is fascinating for those of us who are so inclined.

Do we really need a chemistry degree in order to choose a motor oil? No. But it's good to remember that all motor oils are not created equal.

It is unlikely that any major motor oil company today is going to produce a really bad product. But is adequate what riders really want? If you are going to change it frequently, if you are going to be a kind, tame rider who never gets on the throttle, well, Harley-Davidson Oil is just fine, as most motorcycle oils probably are. But if you're the kind of rider who puts your machine through its paces, who makes modifications that bump your horsepower to the next level, if you're cranking it up and you want to know your engine has the protection it needs, or simply want the best, a premium synthetic motorcycle oil is the lubricant of choice.

Here's how I see it. Additive chemistries are just that: additives. They are chemicals that have been added to the base stock. These chemicals have various functions. But the final product can only be as good as the foundation you build on. Quite honestly, there would be no synthetic motor oil market if the only thing you needed to do to get premium performance from crude oil was put some chemicals in it. The fact is, petroleum has its limitations. All oils are not created equal.

A premium product does not end with the base stock. Additive selection makes a difference. Chuck Goldmann notes that not only is selection important, the process of assembling the motor oil is also important. In short, you want an experienced manufacturer who understands the interrelationship of the various components of the lubricants being produced. It is not simply a matter of putting ingredients together.

Harley-Davidson® noted, correctly, that "you cannot distinguish between a good motor oil and a better motor oil by additive metals analysis alone." Remember, though, that this is not the same as saying additive metals don't make a difference. The truth is a manufacturer can skimp on certain chemicals to keep costs down and consumers will not notice anything, even though there are consequences. I would like to use an example from a different industry that readers may understand.

In the realm of house paint, not all paints are created equal. If you take a really cheap white paint, you may need three coats of paint to cover a medium colored surface. If you take a very high end professional paint, you can cover that surface with one coat. I once painted a black door white with a single coat of premium high quality paint. All of these paints look white inside the pail. But the high quality paint has a higher additive content. By increasing the amount of titanium white, an additive, you can get better coverage. This additive is expensive, however, and people often do not wish to pay the price, so paint manufacturers produce low end products to satisfy the consumer who wants to buy on price. Savvy consumers who value their time are willing to pay more to get the better, one-coat coverage.

When it comes to additives, Amsoil spends more so that the oil exceeds, not simply meets, the demands of a long life lubricant. High TBN, and sufficient zinc and phosphorous, helps reduce engine corrosion and wear, increases oil service life and reduces maintenance costs.


What does all this mean for readers? There are two very real and noticeable benefits for bikers who use a premium synthetic motorcycle oil like Amsoil. First, the engine runs cooler. Reduced friction results in cooler operating temps. If you are riding hard out on the desert or stuck in city traffic in L.A., you can definitely feel the heat from your hog. What can you do? You can't install air conditioning. You can use a premium synthetic and run perceptibly cooler.

The second benefit, extended drain intervals and longer service life, is appreciated by many Amsoil users. Instead of having to change the oil midway through the season, you simply change the filter. The oil's additive package is beefy enough so that the oil is good to go for up to three times the equipment manufacturers recommendation or one year, whichever comes first. If you are uncomfortable with extended drains you can still change at normal intervals and needn't have fear if inconveniences cause you to go beyond your normal oil change interval.

Another, less noticeable but very real benefit of a beefy additive package in a synthetic is this: at the end of the year, bikers in northern tier states also appreciate knowing that the anticorrosive characteristics of a premium synthetic are better than their petrol counterparts. There is less likelihood of rust and pitting on parts inside the engine as it sits idle through the winter.


A major concern many riders have had pertains to the warranty issue. Harley-Davidson has created the impression that if you are a rider who uses any oil besides Harley-Davidson oil, you will void your warranty. Many motorcycle shops believe this to be the case, although the writer of the November Harley-Davidson article indicates that "in a pinch Harley-Davidson recommends that a rider use one of the API C category oils as a substitute for Harley-Davidson 360." Nevertheless, the impression is out there that the warranty will be voided if you use another product, and since the bike has cost a good chunk of change, no one really wants to gamble with that much money on the table. Fortunately, there is a law called the Magnusson-Moss Act that says, in laymans terms, an OEM cannot require a consumer to use an OEM part or fluid in order to maintain warranty coverage unless that part or fluid is provided free of charge.

I can't speak for other oil companies, but I can say that Amsoil warrants its oil against lubrication related failure. We have 28 years experience and wouldnt be in business today if engine failures were a problem. We have more experience with synthetics and extended drain intervals than anyone in the industry.


Don, in his April column, wrote: "There is nothing wrong with Harley oil, and it is a good fossil oil to run in your bike. It is just that modern marketing can be very skillful in making the consumer paranoid about using anything but the manufacturer's suggested oil. There are better oils out there. Period." Right on, Donny. I can't agree more.

It would appear that Harley-Davidson has not made it a goal to empower riders to make choices. They have made a marketing decision, forced reliance on Harley-Davidson. Is this what riders want? Do riders really want to be stuck with no options regarding motor oil selection? Do riders want to be forced to use inferior oil when they know other products can provide better protection, reduce heat, increase horsepower?

They say it is not a marketing issue, however, Harley-Davidson has chosen not to help their customers use other products. There are no factual reasons for this. Their oil does not offer the benefits of a synthetic, and it is clearly a marketing move.

A lot of riders change ignitions and make other modifications to run their Harleys at higher RPM, modifying their bikes to get more horsepower. This puts more stress on the engine, creates more heat. These modifications may also present warranty problems as well. Perhaps even a majority of riders modify their bikes to increase performance, and most really ought to be using a higher performance motor oil. It would appear that Harley-Davidson is not interested in helping these riders.

With more heat generated, oil breakdown does occur. The graph on oxidation performance in the December issue shows a shocking difference between HD 360 and Mobil 1 V Twin oil. This chart and many other tests for benchmarking performance prove emphatically the superior capabilities of synthetic motor oils. Why, then, has Harley-Davidson refused to promote the performance benefits synthetics offer? It might be that being affiliated with one oil supplier for so long has slowed Harley-Davidsons adoption of advancements in lubrication technology.


Synthetic motor oils offer numerous performance advantages over conventional petroleum based products. For this reason, in nearly every other market from trucks to cars to heavy duty equipment to sport vehicles synthetics have been greeted with increasing enthusiasm. The technology is proven. The benefits are many. There seems to be no good reason why motorcycle owners should be discouraged from embracing this trend.

Motorcyclists Who Demand the Best Choose Amsoil

Team Green RacingTeam Greene Racing N.Y.I.R.P MOTORCYCLE CLASS

"This will be my third season running Amsoil Motorcycle Oil in my 1134cc Suzuki Dragbike. After testing Amsoil 10W-40 Motorcycle Oil at the track, the clutch performed flawlessly. We actually noticed a slight decrease in our 60' times, and better yet, as the season progressed we saw less clutch plate wear. Prior to switching to Amsoil Motorcycle Oil, I would change oil in the dragbike every month, but now I have tripled the drain intervals."

Cory Greene
2001 N.Y.I.R.P. Motorcycle
Class Champion

Miller RacingMiller Racing AMA/FASTTRAX

"I run a Yamaha R6, which is the dominant bike on my racing circuit. Of all the guys who run these bikes, the only ones that don't use up any oil are mine and the others who use the Amsoil products. My engine has run great all season thanks to Amsoil lubricants."

Mike Miller

If you would like more information on Amsoil Motorycle oil, becoming a dealer, or ordering Amsoil products, please either call or email us at: or 419-396-6201, Monday through Friday, 9-5, and Saturday, 9-3.

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