Agree. I think most are overthinking the issue. All Honda GWs and most other bikes with wet clutches prior to the onset of the JASO standard in 1999 required a high detergent good quality oil with no additives. The present API standard that replaces the API standards of the bikes pre-1999 is an API SN standard.robin1731 wrote:That myth is all over the place. As long as it is rated for a wet clutch it will work fine. I used synthetic oil in race bikes back in the late 70's with no issues.5speed wrote:I'm sure I read somewhere here that synthetic was to slippery for our clutches.
As long as the API donut has the lower half blank: and is API SN standard it is good to use in a wet clutch application. The blank lower half indicates that there are no friction modifiers/additives.
The JASO standard is in two parts - MA and MA2. The MA spec is an oil that can be used in wet clutch applications and has no friction modifiers/additives. JASO MA2 is the same as the JASO MA except that it can also be used with catalytic converters.
Some are using an oil that is the API CJ-4 standard, but this is used mostly for heavy duty engines such as diesels running on ultra-low sulfur diesel (ULSD) fuel, are critical for the durability and performance of 2007 and newer engines that utilize advanced emission control technologies. API CJ-4 oils are formulated for improved wear protection, deposit and oil consumption control, soot-related viscosity control, prevention of viscosity loss from shearing, used oil low-temperature pumpability, and protection from thermal and oxidative breakdown when compared to previous API performance categories. From this description I would surmise there may be friction modifiers/additives in the oil.
When going for oil, get an API SN spec oil with no friction modifiers/additives and has an API donut that has the lower half blank. If there is no API donut on the oil, check on the net for the MSDS sheet and the various specs should be listed on this sheet.
Whether you use synthetic or mineral is really a personal preference.
Just a few thoughts to consider. Cheers