Oil in Bikes

[YFZ-FoFiddy-TC]

What weight oil do you guys run in the 450's? I usually run 10-40 but today when I picked up some oil it was 20-50 and I thought it was 10-40. What are the differences in them and what do most of you guys run?

[standardryder]

20-50 is just a little thicker, so it wont be as efficient in colder weather. As long as you change it out before winter youll be fine. I use 10-40 myself year round.

[Jim417mx]

I use to run amsoil 20w50 year round, I had zero problems, but I have switched to 10w40 due to the fact that thats what alot of people run.