WHY HARLEY OWNERS CHOOSE AMSOIL
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. 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.

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