So here is my issue I have a used 150 Wolf scooter not starting. I have fuel,spark,and compression. I recently replaced stator and flywheel. I have a feeling it might be ignition timing but not sure. When I try to start it it almost starts but won't and every once in a while it will make a loud pop like a misfire in the chamber. And I'm not real sure exactly how to check or fix the timing I know how to find tdc but after that I'm not sure how to go about making sure timing is correct. I still have old flywheel with original timing marks if this helps. Any help is appreciated thanks.