What does the JASO MA and JASO MA2 Motorcycle Oil Standard Mean?
In 1998 the Japanese Automotive Standards Organization (or JASO for short) developed a grading system for motorcycle oils.
The grading system measured (among other things) an oils ability to resist clutch friction (or slippage), protection offered against engine wear and pitting in the gear box.
What is synthetic motorcycle oil?
There are basically two types of synthetic base oil used in synthetic motorcycle oils.
The most common is the Group 3 – which are a really a super refined mineral (also called hydrocracked), the commonest being XHVI, which is made by Shell and promoted by them as a synthetic, as they are a very big company, and XHVI is a lot cheaper than a Group 1 (proper) synthetic, most folk go along with them!
The proper Group 1 synthetics are man made blends of PAO’s (polyalphaolefins) and Esters, being specified for stability and lubricity.
What do the letter and numbers mean on motorcycle oil bottles (e.g. 10w40)?
As well as being defined by their type (e.g. Synthetic, Semi-Synthetic or Mineral), motorcycle engine oil is also defined by it’s thickness (or viscosity). The viscosity rating is normally displayed on the oil container by a series of 2 numbers separated by a letter (e.g. 10w40 or 20w50).
This grade is also known as the SAE grade of the oil (e.g. SAE 10w40). SAE stands for the Society of Automotive Engineers and they are one of the the bodies responsible for publishing the standards that govern Automotive Oils (2 other bodies that grade oils are API, American Petroleum Institute and JASO, Japanese Automotive Standards Organization).