28-10-11, 11:38 PM
(28-10-11, 06:57 PM)Major Rant link Wrote: ... ALL OIL degrades in use and none of them can be trusted to stay within their viscosity window more than a few K miles...
Indeed, but presumably Yamaha are aware of that too. If they'd cynically increased the service interval from 4000 to 6000 miles in order to sell more spares they'd soon find a reputation for selling vehicles that don't last isn't good for business. Unless you're seeing if you can get a world record mileage out of a Fazer engine I can't see the point in changing oil more frequently than the manufacturers recommend.
I tried to find some details on the Tesco website about their fully synthetic, aside from a choice of 5W30 or 5W40 the information was limited to advice that nutritional content is subject to change. :lol
Since viscosity modifiers supposedly get chewed up worse by the higher speeds in bike gearboxes, wouldn't an oil like that (with a wider range than required) suffer more than a 10W40?