Comment number 1:
As the Yamaha owners manuals state, don't use any oil labled "CD" or "Energy conserving II" - See p. 7-15 of 2009 FZ6R manual. Additives in these oils can cause clutch problems.
Number 2:
Might want to consider MA oils - Extract below:
Another institute that certifies oils is called the Japanese Automotive Standards Organization, JASO. One wonders why this Japanese organization has an English name. . . In any case, they have two classifications for motorcycles, "MA" and "MB." MA is the one you want. MB is like the API SL category, it's got all those nasty friction reducing chemicals that may scare your clutch into misbehaving. Again, there is an official JASO seal if the oil 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 MA. If the oil manufacturer did their own testing, instead you'll see just words like "Meets or exceeds JASO MA standards."
Number 3:
My WR250R Yamaha dual sport engine gets a serious work out, since I ride it fast on paved and dirt roads. I am usually running between 7000 and 11000 RPM, often at full throttle because it's a small engine. I have tried the following oils to see if there was any difference in engine noise, clutch action, or transmission smoothness:
Penzoil, Mobil 1 "4T" synthetic, Valvoline M/C "MA" rated, Maxima Maxim 4 stroke - all 10W-40 weight. I found no difference between them.
At this point I am planning to stick with the Valvoline because it's below $4 per quart, available locally, and is MA rated. I do change oil every 1500-2000 miles, so I'm sure it will do fine.
