I have a 06 ttr 50 with a gytr pipe. It has run for a year with no problems, and never at full throttle. After a hour of ridding the bike was brought home and would not start. The bike has spark and gas comes out the over flow if I open the screw. The spark plug does seem dry when I remove it, but I have tried putting a little gas directly into the whole. Still would not fire. The carb will be coming off next. Hope someone can help, I am out of ideas