Study on 4-Stroke Engine Oils for Motorcycles: Engine Characteristics and New-Specification Oils

In 1990 AAMA and JAMA established the ILSAC/GF-1 Standard and API established its new SH Standard. The main feature of these new engine oil standards are lower viscosity and lower friction. AAMA and JAMA are preparing to establish the ILSAC/GF-2 Standard in 1997 and the ILSAC/GF-3 in 2000.

Motorcycle engine oils have been produced on the basis of automobile oils with minor modification so as to ensure a worldwide availability of motorcycle oils. Motorcycle industries are concerned; that is, based on the new standards for automobile engine oils, do motorcycle oils truly conform with the required performance of motorcycles?

According to this study, friction coefficient and viscosity must be considered to select motorcycle engine oils.