This
And this 20w50
And burned a tank of gas....
Fuel economy is up slightly. (statistically a wash)
Gears shift smoother.
Engine case is notably quieter.... Changing oil every month so not a fresh oil
used oil kinda change..... This is a viscosity change.
This is all in 80F (26 2/3) morning, 100F (37 3/4) afternoon riding.
My conclusion... In Southern US states in mid summer a thicker oil is a good
thing. However... I would never run 20/50 in the cooler/cold months.
I will continue to run 20w50 for at least 2 more months....
I will let you know if my oil pump fails or my motor blows up
Disclaimer:
Owners manual says 20w50 IS an option.
I decided to pursue this option even though the fill cap for the engine case clearly states 10/40.
If you follow my footsteps and have an engine failure it's not on me cuz I told yall the disclaimer 8~P
If your motor is precious to you use what is printed right there at the fill plug 10w40....
I also recommend you read your bikes owners manual recomendations though