A multigrade such as 10W-40 describes viscosity behaviour across cold and hot conditions. It does not, by itself, tell you whether an oil suits a motorcycle wet clutch.
Look for the viscosity and standards required by the owner’s manual. Motorcycle-specific JASO classifications can matter where the engine and clutch share oil.
More expensive is not automatically more appropriate. Correct specification, genuine product and timely changes are a stronger maintenance strategy than improvising from marketing claims.
