I had a similar problem at about 16000 miles. cutting out at random times while riding, stalling/unable to maintain idle while stopped. had it in 2 shops, one w/ certified yamaha mechanics. they spoke with yamaha technical reps in california ( I also spoke w/ them). shop wanted to install a Power Commander, which would have voided warranty. The problem apparently ended up being a faulty fuel pump, which was replaced. no further problems, except rarely engine quits when coming to a stop after 10-15 mins on the freeway. then it starts and runs ok again.