I have been using my 70 cc gas engine bike to commute to and from school 10 miles for the past few weeks, and it has been starting up and running completely fine. I went for a test drive this weekend and it wouldn't start. I checked the cdi wire connections, didn't help. I pulled the spark plug, turned over the engine with it out, and it is definatley sparking. I tried to start it with the choke on a few times, then I tried without it. Usually it starts within 10-20ft of when it is engaged but today I was pedaling a good 200 feet straight and was getting nothing.