Rotella T 15w-40 does the job just fine
i have had good luck with Amsoil and Castrol RS rt 4:ride:
+1 on rotella 15w40! years of use without issue.
Gee what a surprise another oil brand war.
I don't use expensive syn's, they're just wallet bait for the average rider IMO.
I did have a immediate clutch slippage issue with an older Honda street bike resulting from swapping to a synthetic lubricant.
I don't care what brand of oil. I DO care more about chain tension, chain lubrication, and air filter maintenence.
I DO care about consistant, TIMELY oil change intervals.
I use Kawasaki 10W40 mineral in ALL my engines. It's been a proven relaible lubricant for the past 30 years, and it's reasonably priced, and convienent for me to purchase at my local dealer.
walmart sells mobil 1 4t synthetic for 8.98 per quart. i've been using that with no ill effects