Motorcycle Repair: oil...10-40 ?, viscosity oil, motorcycle oils

Question
Hello Bill,
I have moved to Thailand and bought a Honda 150cc four stroke...It was recomended that I use a 10W40 multi viscosity oil...The temperature her does not vary moe than 80 degrees to 95 degrees Farenhight all year for the most part..What would you recomend?
Thanks Rolfe

Answer
Rolfe, despite the constant temperatures, just like here in Hawaii, the recommendations are probably correct for that machine in that climate. Those motors get hot in that climate and under those road conditions, so the 40w end of that rating is needed under extreme conditions like that.
A small bike like that working hard all the time, needs all the help it can get.

If you just bought it and are breaking it in, then go to 10W-30 for the break-in period, then switch back to 10W40, as recommended, using motorcycle oils NOT automobile oils, which breakdown rapidly due to the shearing action of the transmission gears.

Bill Silver