Hi I have a 31cc 4 cycle engine on a friction kit. ? one the inside of the clutch housing has been worn smooth, is there any benefit, to roughing it up, or is smooth just the nature of the beast. Next is the oil, the instructions did not say and the with the dip stick Would you measure the oil as the stick is unscrewed slide in and out and measure, or screw in and and then out. it only has about 3.5 oz of oil when filled to the point where I can see it at the bottom of the tube and sloshing back and forth to see it. Even with it unscrewed the mark seems to low for it to be right, China tech ya know.... I do not want to over fill or under fill this lil motor this reads badly for that I am sorry. This is the engine, I hope this works Thanks and happy biking!