JASO Revises Motorcycle Oil Specs


SINGAPORE – The Japanese Automotive Standards Organization is working on a two-year schedule to update its specifications for both two- and four-stroke motorcycle engine oils. An official from the organization told an industry conference here that revisions will replace outdated engine tests and adapt to the growing focus on fuel economy.

Yashiro Yoshinobu, of Yamaha Motor Co., made his comments Thursday during a presentation at the Fuels & Lubes Asia Conference.

JASOs engine oil specifications are used in Japan and throughout Asia where Japanese motorcycles are popular. The specifications being revised are JASO M345 for two-stroke engine oils and JASO T903 for four-stroke oils. The organization has a target date to complete both revisions by April of 2016.

Yashiro acknowledged that some have suggested JASO retire M345 because of the motorcycle industrys shift to four-stroke engines. But large numbers of motorcycles with two-stroke engines remain in service, even though production of new ones has dwindled. Yashiro also noted that the majority of handheld outdoor equipment uses two-stroke engines and hence two-stroke engine oils.

If the industry is to continue using M345, Yashiro said, it needs to replace the Honda AF27 engine, which is used to conduct the M340 lubricity test and the M341 detergency test. The Honda AF27 is no longer produced, and replacement parts for engine test stands are no longer available.

JASO is also working to replace an engine used for T903, Yashiro said, because there has been dissatisfaction with the existing equipments performance on tests for lubricity, detergency, smoke generation and exhaust system blocking. A committee is now assessing whether the Yamaha ET-1 would be a good replacement.

JASO is also working to devise a test for an oils ability to prevent gears from pitting. Yashiro said such a test will become important as the industry moves toward thinner oils in an effort to improve fuel economy. The potential for pitting will also rise as concerns about poisoning new emissions control equipment requires formulators to cut back on their use of phosphorus, which is found in many anti-wear additives.

It is essential to add a gear-pitting test to future JASO standards, he said.