I always used M1 FS 5w40 in everything with an engine with pretty good results regarding OCI, oil consumption, etc. Castrol Edge and Shell Helix are good options when M1 plays hide and seek.
I own a 150cc mopped with a 25k+ miles on it and mechanics are impressed with its particular engine condition except that it suffers from oil dilution in the last couple of years. The manufacturer calls for 10w30 or 5w40 so I opted for the later since it is more appropriate for ambient temperatures all year long and I use it for my car as well.
A lot of people advice me against the 5w grade and say that wide spread grades are less shear stable and that 20w50 is a better option. (Summer can be north of 100+ F) I'm quite reluctant to believe that 20w50 is necessary in a small air cooled engine application and I used it once and the engine seems to feed on it . And FS 5w40 is a robust PAO/GTL based that seems to be almost universal in all conditions and it barely consume only 150 ml from a total of 1000 ml in 700 miles compared to 400 ml running Dino 20w50. Should I change to higher viscosity 20w50 synthetic to get better Noack? And if you agree on 20w50, would you please recommend me a few good oils that are not JASO MA or inferior MB rated? I need something Full SAPS, PAO based because GTL may fall short in this viscosity range AFAIK. This engine really runs hot (Noack is a crucial property of the oil)
I own a 150cc mopped with a 25k+ miles on it and mechanics are impressed with its particular engine condition except that it suffers from oil dilution in the last couple of years. The manufacturer calls for 10w30 or 5w40 so I opted for the later since it is more appropriate for ambient temperatures all year long and I use it for my car as well.
A lot of people advice me against the 5w grade and say that wide spread grades are less shear stable and that 20w50 is a better option. (Summer can be north of 100+ F) I'm quite reluctant to believe that 20w50 is necessary in a small air cooled engine application and I used it once and the engine seems to feed on it . And FS 5w40 is a robust PAO/GTL based that seems to be almost universal in all conditions and it barely consume only 150 ml from a total of 1000 ml in 700 miles compared to 400 ml running Dino 20w50. Should I change to higher viscosity 20w50 synthetic to get better Noack? And if you agree on 20w50, would you please recommend me a few good oils that are not JASO MA or inferior MB rated? I need something Full SAPS, PAO based because GTL may fall short in this viscosity range AFAIK. This engine really runs hot (Noack is a crucial property of the oil)
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