What is JASO in Engine Oil?

JASO stands for Japanese Automotive Standards Organization which was created as an alternative to the API specifications, as API was not able to fulfil the requirements of the Japanese engines.  Also,  until 1998,  car oils were used for the motorcycle engines as well,  which did not produce a favourable outcome. With the passage of time, many modifications were made in the car oils which in turn proved to be good enough for car engines but were not at all good for motorcycle engines. This is where JASO came to the rescue and started producing motorbike oil.  In 1998, JASO introduced the JASO T903 for 4-stroke motorcycle oils. 

JASO 4T specifications 

There are four major specifications under this category.  

JASO MA

It consists of oils for motorcycles that possess wet clutches. The best thing about these oils is that they are non-friction modified and that’s why save the clutch from slipping.  They are especially used for 4-stroke motorcycles that have one oil system for engine, gearbox and clutch. In 2006, two other specifications were added to this category namely MA1 and MA2.

JASO MA1:

This specification consists of the oils that are used for motorcycles that do not require same oil for engine, gearbox and clutch.  They require different oils for all these parts. 

JASO MA2:

These high standard specification is for the latest, up to date motorcycles which possess catalytic converters in the exhaust system. 

JASO MB

The motorcycles with automatic transmission use JASO MB.  Unlike JASO MA, these are friction modified.  They should never be used in place of MA oils,  as they will cause the slippage of the clutch.  They are the best choice for scooters.  

JASO 2T specifications 

JASO introduced the following specifications in order to lessen or avoid the production of excessive smoke and exhaust blocking because of the API TC specifications.  These specifications are of four categories. 

JASO FA 

JASO FA deals with the lubrication capability,  exhaust smoke, exhaust blocking, initial torque and detergency.  

JASO FB 

This is the higher version of JASO FA and correlates with the ISO Global Specification EGB.  It performs the similar functions as that of FA, only with the increased lubrication capability. 

JASO FC

This specification provides your motorcycle engine with quite higher standards for exhaust system blocking,  smoke and detergency.  

JASO FD

This specification has the higher detergency requirement and the rest of the characteristics are similar to JASO FC. 

All of the above 2T are in correspondence with the ISO global specification EGB.  For a long period of time,  car oils were used for bikes and were usually friction modified.  These oils used to cause the pitting of gearboxes and slippage of clutches. JASO introduced all the above mentioned specifications to work things out for motorcycles and to also provide better oil standards tu the modern Japanese engines. These JASO specifications have helped a lot in getting rid of excessive smoke and maintaining the engines in their healthier forms for the maximum time period.