Everything was running fine and then this problem started. The bike will fire a few times and sometimes and can even get it to rev but as soon as i let the throttle go it dies. I've tried everything at this point. There's spark, fuel, no leaks. When testing the spark plug against the head no there would be no spark if i turned it slower but with a decent kick there was a strong spark. I don't know if this is normal i've never payed that much attention to how fast it needs to spin before spark is made.