JASO M345 is a quality classification standard for
two stroke
A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which re ...
engine oil
Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, deter ...
s for
engines
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power gen ...
of
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
ese origin. It was introduced by the
Japanese Automotive Standards Organization
The Japanese Automotive Standards Organization () is an organization that sets automotive standards in Japan, similar to the Society of Automotive Engineers (SAE) in the United States. JASO establishes standards for various types of engine oil, i ...
(JASO) in 1994 as JASO M345-93 with the quality levels JASO FA, JASO FB and JASO FC – with FC setting the highest standard. It was revised in 2004 as JASO M345:2004 which discontinued the FA level, and introduced the new JASO FD level – the FD level supersedes JASO FC as the highest rating. ISO 13738 is a similar, but stricter, specification.
The different quality levels set requirements with regard to properties such as minimum
lubrication
Lubrication is the process or technique of using a lubricant to reduce friction and wear and tear in a contact between two surfaces. The study of lubrication is a discipline in the field of tribology.
Lubrication mechanisms such as fluid-lubr ...
, minimum
detergency, maximum smoke and maximum deposits. A two stroke engine oil is granted the official
JASO seal if it has been independently tested. The seal is a rectangle; in the upper quarter of the rectangle will be a serial number, and the lower three quarters will just have the letters FB, FC or FD.
Overview
JASO FA – original spec established regulating lubricity, detergency, initial torque, exhaust smoke and exhaust system blocking. Supposed to exceed
API-TC.
JASO FB – improved requirements over FA with regard to lubricity, detergency, exhaust smoke and exhaust system blocking.
JASO FC – lubricity and initial torque requirements same as FB, however far higher requirements over FB with regard to detergency, exhaust smoke and exhaust system blocking.
JASO FD - same as FC, except with far higher detergency requirement.
References
{{Reflist
External links
JASO Engine Oil Standards Implementation PanelIPONEATV OutdoorsThe Motor Oil Store 2T
Motor oils
Lubricants