two cycle oil/standards
I got this from lubrizols website. Compare the test specs for a API TC aircooled oil vs a ISO EG-d oil its very easy to see that the iso oil is far superior. BTW API TC is equivelant to JASO FA. The api doesnt formaly test for tc(its obsolete) anymore as the test engines are not available anymore.
"For air-cooled two-stroke engines, lubricating oil performance is classified according to API, JASO, ISO and TISI (Thai Industrial Standards Institute). For outboard engines, oil performance is classified according to NMMA.
Air-cooled engines: API TA, TB and TC are the oldest performance categories for two-stroke air-cooled engines, although API TC has been the most prevalent and demanded category. At present, the API TC detergency test is run using previously used cylinders and slightly oversize pistons because Yamaha no longer provides the test parts. Also, a new low-ash reference oil is being used instead of the original ashless oil because the ashless oil had experienced hot ring sticking problems over the last decade. Only a limited number of test parts are available for the API TC detergency test.
In 1994, the Japanese Automobile Standards Organization (JASO) defined a specification that describes three quality levels for low-ash air-cooled two-cycle engine oils: FA, FB, and FC. Lubricant performance is assessed according to four performance criteria: detergency, lubricity, exhaust blocking, and smoke. Performance of a candidate oil is rated against that of a reference oil.
The thrust of the JASO specification is the low-smoke requirement, which is especially stringent for the FC performance category. This requirement arises from the need to alleviate smoke problems in Asian cities. JASO FC will be the predominant performance level.
An International Organization for Standardization (ISO) Global Specification for two-stroke oils has also been developed. This specification standardized the requirements described in the JASO document and established an additional, higher international performance level. This standard is expected to be established in late 1998.
The difference between the JASO and ISO specifications is the inclusion of a performance category higher than JASO FC and an additional requirement to evaluate piston varnish. These oils will be required to provide higher detergency and ring-stick protection than the JASO oils.
JASO and Proposed ISO Two-Cycle Index1 Ratings
ISO Global Specification — GB GC GD
JASO Specification FA FB FC —
Lubricity, min 90 95 95 95
Initial Torque, min 98 98 98 98
Detergency, min 80 85 95 125
Exhaust Smoke, min 40 45 85 85
Exhaust System Blocking, min 30 45 90 90
Piston Varnish2, — min 85 90 95 95
I got this from lubrizols website. Compare the test specs for a API TC aircooled oil vs a ISO EG-d oil its very easy to see that the iso oil is far superior. BTW API TC is equivelant to JASO FA. The api doesnt formaly test for tc(its obsolete) anymore as the test engines are not available anymore.
"For air-cooled two-stroke engines, lubricating oil performance is classified according to API, JASO, ISO and TISI (Thai Industrial Standards Institute). For outboard engines, oil performance is classified according to NMMA.
Air-cooled engines: API TA, TB and TC are the oldest performance categories for two-stroke air-cooled engines, although API TC has been the most prevalent and demanded category. At present, the API TC detergency test is run using previously used cylinders and slightly oversize pistons because Yamaha no longer provides the test parts. Also, a new low-ash reference oil is being used instead of the original ashless oil because the ashless oil had experienced hot ring sticking problems over the last decade. Only a limited number of test parts are available for the API TC detergency test.
In 1994, the Japanese Automobile Standards Organization (JASO) defined a specification that describes three quality levels for low-ash air-cooled two-cycle engine oils: FA, FB, and FC. Lubricant performance is assessed according to four performance criteria: detergency, lubricity, exhaust blocking, and smoke. Performance of a candidate oil is rated against that of a reference oil.
The thrust of the JASO specification is the low-smoke requirement, which is especially stringent for the FC performance category. This requirement arises from the need to alleviate smoke problems in Asian cities. JASO FC will be the predominant performance level.
An International Organization for Standardization (ISO) Global Specification for two-stroke oils has also been developed. This specification standardized the requirements described in the JASO document and established an additional, higher international performance level. This standard is expected to be established in late 1998.
The difference between the JASO and ISO specifications is the inclusion of a performance category higher than JASO FC and an additional requirement to evaluate piston varnish. These oils will be required to provide higher detergency and ring-stick protection than the JASO oils.
JASO and Proposed ISO Two-Cycle Index1 Ratings
ISO Global Specification — GB GC GD
JASO Specification FA FB FC —
Lubricity, min 90 95 95 95
Initial Torque, min 98 98 98 98
Detergency, min 80 85 95 125
Exhaust Smoke, min 40 45 85 85
Exhaust System Blocking, min 30 45 90 90
Piston Varnish2, — min 85 90 95 95
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