The motorcycle oils industry is currently going through an important period of specification change. Major revisions have been proposed to the JASO M345 (for 2-stroke) motorcycle standards surrounding replacement of engine tests and inclusion of new engine tests. The JASO T903 (for 4-stroke) has recently been updated in 2016 for changes related to the friction test.

Motorcycles - Four-Stroke Cycle Gasoline Engine Oils (JASO T903)

UPDATE May 2016 - the new specification has been launched. Visit the 4-stroke specification page to learn about the updated specification.

Two-Cycle Gasoline Engine Oil Performance Classification (JASO M345)

Two-stroke products continue to be sold globally and current worldwide production volumes for 2-stroke general purpose engines are to the tune of 24 million units. While the production and sales of the 2-stroke engines for motorcycle use will decrease, 2-stroke engines for hand-held power tool use (such as brush cutters and chain saws) will continue to have a presence in the market.

The current 2-stroke oil standard (JASO M345) specifies the use of the Honda AF27 engine for evaluating Lubricity and Detergency characteristics and the Suzuki SX800 engine for evaluating Smoke and Clogging characteristics. However, the industry is facing difficulty in running these tests due to the discontinuation of these engines and non-availability of parts. These issues create an important need for the continuation and revision of the 2-stroke oil standard in the future.

Since 2013, LEMA (Japan Land Engine Manufacturers Association), with the support from JAMA (Japan Automotive Manufacturers Association), has been working on replacement engines that are more representative of the technologies used today for the standard tests (Lubricity, Detergency, Smoke and Clogging). The new candidate engines, which have been incorporated into the revised JASO M 345 Implementation Manual (July 2018), are Husqvarna-Zenoah EBZ6500 and Yamaha ET-1.

The revised “Two Cycle Gasoline Oil (JASO M 345) Application Manual” which includes these new tests, for JASO On-File oil qualifications, will be issued by 2020.

JAMA is eager for the industry to adopt its specifications; the goal is to empower end-users to select the right oil for their motorcycles, and other small engine equipment.

Contents of this article is based on JAMA's presentation used at the 2014 F&L Asia event. If you have any questions, contact your Lubrizol representative.