If the screw quits coming loose then ya got it. Good deal bro. One of my very first engines ran like yours. Luck of the draw I guess. A bone stock China girl hitting 40mph is rare. I sold mine to a friend and he got it stolen in less then a week. I had a buddy run along side in his car to clock it. When it hit 40mph I backed off cause I didn't wanna blow it up. I named that bike ZIPPY. I name all my bikes, Doesn't everyone?