Motorcycle Oil

Engine oil is the single most important part of routine engine maintenance. There are more myths, misunderstandings and urban legends regarding engine oil, than any other mechanical thing out there. Let’s demystify the engine oil and help you make the best decision for what type of oil to purchase for your motorcycle.

When it comes to motorcycle engine oil there are 3 ways you can help improve your motorcycle’s mileage and insure that it delivers good economy for a long time.

1 – understand the functions of oil in the engine

2 – choose the proper oil for various operating conditions

3 – change the motorcycle oil and filter at proper intervals

If you look at all the parts in the motorcycle engine that oil keeps lubricated you’ll get an appreciation for importance of proper motorcycle oil maintenance.

Motorcycle engine oil is a lubricant and it is its’ primary function but it also performs a number of other functions which are vital to the life and performance of your engine. Motorcycle engine oil also dissipates heat and makes parts run cooler, helps reduce engine noise, engine oil prevents rust and corrosion, acts as a seal for pistons, rings and cylinder walls, combines with oil filter to remove foreign substances from the motorcycle engine.

There are several types of motorcycle engine oils out there. Engine oid service classifications are designated by the American Petroleum Institute based on the chemical composition of a given type of oil and testing of samples. The ratings include “S” for normal gasoline engine use and “C” for commercial use. The S rating has been supplemented with various letters, each one representing the latest and greatest rating available at the time of it’s introductions. During the recent years these ratings have included SF, SG, SH and SJ.

Since oil is so important to the life of your motorcycle engine, you should never use and oil of questionable quality. Oil should also be selected based on temperatures for coming months. Please refer to your manufacturers manual for their recommendations.

In addition to the classification of the American Petroleum Institute your oil should be of a viscosity suitable for the outside temperature in which you’ll be riding in. Oil must be thin enough to get between the close tolerance moving parts it must lubricate. It must also be thick enough to separate them from a slippery oil film. If the oil is too thin it won’t separate the parts, if its’ too thick it can’t squeeze between them in the first place. In either case excess friction and wear takes place.

According to the Society of Automotive Engineers (SAE) viscosity classification system, oil with a high viscosity number such as SAE 40 or 50 will be thicker than one with a lower number such as SAE 10W. The W indicates that the oil is desirable for use in winder driving. How to translate the codes for oil: For example, a 10W40 oil is to have the viscosity of a 10W oil when the engine is cold and 40 when the engine is warm. In cold temperatures below 0 degrees F you should use oils such as 5W20 or 5W30.

For all oil specifications please refer to your motorcycle manufacturers manual.

Oils are also enhanced with several different additives:

Pour point depressants which help cold starting by making the oil flow more easily at low temperatures.

Oxidation and Bearing Corrosion Inhibitors which help to prevent the formation of gummy deposits which can take place when engine oil oxidizes under high temperatures.
Rust and Corrosion Inhibitors protect against water and acids formed by the combustion process.

Detergents and Dispersants clean up the products of normal combustion and oxidation while dispersants keep them suspended until they can be removed by filter and oil change.

Foam Inhibitors prevent the air bubbles which can be caused by tast moving engine parts whipping air into the oil.
Viscosity Index Improvers reduce th rate at which an oil thins out when the temperature climbs.
And

Friction Modifiers and Extreme Pressure additives which are valuable in boundary lubrication where there is metal to metal contact due to the absence or breaking down of the oil film between moving parts.