When to change motorcycle oil?

The manufacturer's service manual will tell you how often you should check your engine's oil level, what type of oil you should use and how frequently you should change it.

As a general rule, engine oil should be changed every 6000 km or so, as great demands are made of it.
However, depending on your driving style, you may have to change it more or less often.

For example, if you make lots of short journeys, engine oil performance will deteriorate, because condensed droplets of fuel will get into it.

Similarly, if you do not use your motorcycle very often, or if you use it intensively, engine oil quality may be reduced depending on the types of lubricant that you use.

As far as the oil filter is concerned, it does not need to be replaced every time the oil is changed. For standard use, it can be replaced every two oil changes.
You should still, however, follow the manufacturer's recommendations.