I have been riding my GT750 on daily basis for the past month and have put 250 miles on it with no problems. A couple days ago, I rode it to work, but when I went to ride it to lunch it wouldn´t start. When press the ignition button, I can hear it whizzing, but it doesn´t turn over. I can kick start it with considerable efforts, but once I get it running, it idles okay, but sputters and backfires out of the carbs when revved up, then quickly dies. It´s always started right up whether electric or kicked. i don´t understand what has gone wrong so quickly and without warning. Any ideas would be appreciated.