HI, you should see a mark/line on the cable/pulley wheel of the oil pump, at full throttle (you might like to check it without the bike running) this should line up with a line/mark on the pump itself. If not adust the cable untill both marks line up.
Does the bike smoke heavy, is the pump worn out, are you using a good grade of oil, is the spark plug the correct heat rating, some other things to think about if all is well and the pump is set correctly, hope this is of some help Hugh,,,,,