I have an 09, 250 proxs with 84hrs on it. I would say one out of ten times, only on holeshot, the motor just cuts out. I can let off throttle and try again and it will go. I always let the motor warm up, but it seems to cut out more after a long idle. It idles fine and runs fine up to wot, but also seems to have a slight miss with just minimal throttle. The previous owner installed an ethanol resistant fuel line and bulb and I have replaced fuel filter and spark plugs. Got any ideas?