It can also be due to oil filters without non-return valves fitted = most cheap filters). Oil drains back into the sump and it takes about 30 secs to fully re-pressurize the oil galleries and HLA's.

If it continues at low to middle revs, clearing at high revs it could also be the oil pump on its way out.

2002 Sporty , Ironman 2.5" spring, 2" body, 15 x 7 ROH wheels, K&N, 15 x 10.5 Simex Centipedes, Powerchip 91.

"Never argue with an idiot. They will bring you down to their level then beat you with experience!"