Those bikes have clunky trans to start with. Definitely change the oil if you haven't already.
Is the oil light coming on while the bike is idling or while ridding?
Are you bogging it down to very low rpm's? (below 700) If so, the oil pressure will droop enough to trip the light.
Is the oil light coming on while the bike is idling or while ridding?
Are you bogging it down to very low rpm's? (below 700) If so, the oil pressure will droop enough to trip the light.