i've got amsoil 20w50 in my V Star 950 right now and am due for an oil change. i typically change the oil about twice a year and usually go close to 5K miles before changing the oil. i live in Austin, TX and we've had a record number of 100+ degree days, but the temperature is about to start dropping this week and whatever i put in my engine now will last until next spring just when the temp starts to hit 80 and 90 degrees again.
so here's my question based on the above information. should i switch to 10w40 during the cooler months, or just stay with 20w50? what's the difference?
additional question: your site's FAQ claims "AMSOIL motorcycle oils are engineered to provide protection up to twice the manufacturer’s recommended change interval or one year, whichever comes first." should we just use this as a general guide that we can push the manufacturer's suggested oil change interval somewhat, or should we take this statement literally that we can actually go twice as long with your synthetic oil before changing it?
Last edited by bevo1981; 08-30-2011 at 09:35 PM.