Hey Paul, I lived in Cambridge for 20 years or so ...
anyway, I think one of those marks is the MAX oil mark. By turning the throttle I think you should be able to see it open and close, so that will tell you which one of the two is the MAX oil marker. Dunno what the other one is but would guess it is either the MIN marker or simply the stock setting. With airbox/jetting etc. mod.s or track riding you might want more oil, but for stock road riding the standard setting might be good.
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MC21 with RS250 engine -for sale-
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