I recently bought a 220 cc motorcycle.Manufacturer recommends 20W50 engine oil.I have seen owners manual of 250 cc motorcycle by another manufacturer where recommended oil viscosity is 10W30.I want to know what parameters are used by makers to provide a recommendations for engine oil and why is there a difference by two manufacturers for almost the same engine displacement


1 Answer 1


Like with AC compressors. Basically a matter of materials chosen for the internal mechanics, oil galleries design and internal clearances. The different combinations of these call for a different oil film thickness and hence different oil viscosities across a temperature range. Same or nearly the same displacement doesn't mean anything because every engine has its own engineering design behind it.

  • Contrary to this theory, I recall filling 5W30 (as per the manual) in our CRV and Grace, but later Honda recommenced 0W20. I felt the engine was quiet and returned better MPG. In a span of 5 years, this switch was made at the dealership. In our W221 engine, initially we were asked to fill 5W40, now MB changed that to 0W30. Hence my question can I use 0W20 on the W221 motor? Commented Aug 16, 2020 at 13:03

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .