the only oil you have to change occasionally is the oil in the rear hub is a very small amount of ep80 gear oil and really doent get very dirty but nether the less change it every 5000 miles.the oil in the 2 stroke tank will never need to be changed it doesnt go off and doesn't get dirty it just gets used up so dont ever let it run out or you will have a big problem with the engine seizing up.
adam bike doctor, February 2010