Why adjust the oil pump on the fly. If you have got it wrong either way you can kill the motor.
The manual, haynes or otherwise will tell you how then leave the bastard thing alone.
Who on earth told you to let it idle for 15 mins. Sweet mercy THATS where the oily crap is coming from. You start a 2stroke and ride away. 30 sec tops. Or the engine oils up. Gumming rings filling the exhaust with crap.