How to choose oil for a BMW motorcycle
Not every motorcycle takes the same oil. Here is what matters and where to find the exact one for your model.
Viscosity: from the manual, not by guesswork
Numbers like 5W-40 or 15W-50 say how thick the oil is cold and hot. BMW gives the viscosity for each engine: for example 5W-40 for the R 1250 GS and 15W-50 for some air- and oil-cooled boxers. A different viscosity changes oil pressure and lubrication. See the right one for your model in its plan.
JASO MA2: because of the clutch
On most motorcycles the clutch runs in the oil. Car oils contain friction modifiers that make the clutch slip. The JASO MA2 standard guarantees an oil made for a wet clutch, and it is what the manual specifies for most BMW models.
API: the quality
API SL, SJ or a newer class shows the oil's general quality. The manual gives the minimum; a newer class is fine.
How much oil
The quantity differs by model and depends on whether you change the filter too. Fill to the manual and check the level at the sight glass or dipstick, on level ground with the engine warm, as described for your model.
Synthetic or mineral
Modern BMW engines are made for synthetic or semi-synthetic oil to the standards above. What matters most is the viscosity and JASO MA2 from the manual; the brand comes second.
Which oil does your motorcycle take?
Choose the model and see the viscosity, the standard and the litres from BMW's manual.