i have the same problem. called a guy at the shop he said, pick front end up for few seconds drop it down and kick it over. this works however he couldnt tell me what was causing the problem.
when I started riding last night, my headlights starting going on and off. if i rev real high they would come on soon as i let off throttle the lights would cut out. checked all electrical connections. none were loose. any ideas what this would be?