Most bikes have it written in the owners manual. But a good rule is to have it done after the first 10 hours or so. The valves may need to be adjusted at this time also. Its a good idea none the less to take it in for them to look it over and recheck all pdi items
it depends on the riding conditions but i ussually service mine at 50 hours but i also run full synthetic oil and the air filter may haved to be checked between services happy mudin