My 05 has about 50 miles on it and has seen mostly slow speed trails. I found a fire road this weekend and opened it up in 4th and 5th. It bogs when you go to full throttle and misfires at higher RPM. The only thing I've done to it is cut the throttle stop per the FAQ. I did let it idle with the choke on for about 2 minutes. Would that have fouled the plug?