I bought a used 2004 crf 250 with all sorts of parts on it including a high compression piston which makes it really hard to start,but once in a while if i fall or if i just turn it off it wont start up again for 30-45 minutes. i have already tried turning off the gas and tipping it on its side then trying to open up the throttle and kick it a couple times but it still wouldnt start. when it does start it rides flawlessly but i dont know why it wont start plz help :bang: because of that bike i have 25 mosquito bites :yell: