Motorcycle oil

Motorcycle Oils are a range of lubricants, including engine oils, which are specifically developed for the unique needs of motorcycles. They may also be used in quad-bikes.

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Motorcycle Engine Oil

The vast majority of modern motorcycles use the same oil to lubricate the engine, transmission, and (with the expception of Ducatis) the clutch. Normal, "car-derived" motor oil is designed just for engines but was historically suitable in motorcycles. However, some of the latest American Petroleum Institute, or API specifications are completely unsuitable for motorcycles with wet clutches. Representative organisations of motorcycle manufactures, particularly Japanese Automotive Standards Organization, or JASO, work with lubricants manufacturers to create "motorcycle-specific" standards for oils, and the relevent oil companies then develop and test oils which are specifically made for motorcycles.

Transmission Lubrication

Motorcycle transmissions, just like all gear-based automotive transmissions can quickly degrade a multi-viscosity, or multi-grade engine oil. Conventional car and truck transmission oils have specific EP, and other specialised anti-wear additives, but these EP additives are not suitable for the combined application of lubricating the engine and transmission with the same oil, as is the norm in motorcycles.

Multi-viscosity car based engine oils contain viscosity increaser chemicals known as VIs that keep the oil from becoming too thin at high temperatures. The VIs are large chemicals that can be sheared between the cogs of a motorcycle transmission. A motorcycle transmission can degrade a 10W40 oil into a 10W30 oil in around a thousand miles.

Single weight oils do not have VIs and aren't susceptible to degradation in the transmission. However, single weight oils do not work well in cold starts. The best solution is to use a motorcycle-specific engine oil, ideally a synthetic oil. Synthetic oil can have a high viscosity range with minimal VIs.

Clutch Lubrication

  With the exception of most Ducatis, most motorcycles have a "wet clutch". In a wet clutch the clutch plates are immersed in oil. Some oils make the friction plates in the clutch slippery so that the clutch doesn't engage properly when shifting gears or the clutch slips when the engine exceeds a certain torque. Some oils contain friction reducing chemicals. These oils are unsuitable for motorcycles. All 5W20 and 10W30 non-motorcycle engine oils have these friction reducers. Oils with a operating wieght of 40 or greater are not required to have friction reducers. These oils are unlikley to cause clutch slippage.

A properly specified motorcycle oil will still allow for the appropriate lubrication and cooling of a motorcycle clutch, whilst maintaining 100% of the drive to be transmitted by the clutch, even under arduous operating conditions.

Cooling Properties

Some motorcycles are air cooled, and rely on the oil to carry heat away from the engine. Synthetic oils are much better than conventional oils at cooling^{[citation needed]}. Conventional oils are comprised of a mixture of different length hydrocarbons. Inside a pipe, the longer hydrocarbon molecules stay near the wall of the pipe and travel slowly while the shorter hydrocarbons quickly move through the center of the pipe. The long hydrocarbons are along the wall and pick up the majoity of the heat from the engine and are unable to quickly distribute that heat to the cooling fins. Synthetic oil molecules are all the same size. Synthetic oil travels down a pipe uniformly and can transmit heat much more quickly than conventional oil. An air cooled engine lubricated by synthetic oil operates at a lower temperature than one cooled by conventional oil^{[citation needed]}.

Some popular major producers of motor oil

• Castrol
• Fuchs Silkolene
• MOTUL
• Pentosin
• Royal Dutch Shell

WikiHow - Change your own oil

• WikiHow - the WikiHow Guide on how to change your Motorcycle Engine Oil & Filter

References

1. All about Oil
2. The Motor Oil Bible eBook
3. Motorcycle Consumer News