Has anyone experienced X Challenge starting issues from cold ? Bike seems ok when warm. Tried usual stuff, change plugs, clean air filter, battery checked etc. We have completed TAT and Oregon/Washington Cascades this summer, (7500 miles of dirt), with no problems, (no flats or any mechanical failures at all), until Washington state, when this cold starting issue appeared. Have started buying premium fuel to see if that was problem but no improvement. Any ideas ?