I was riding my bike the other day. I took it to work and everything was fine. I let my friend at work ride it and as soon as he lowered the rpms it died. After that every time I start it I have to keep the rpms running high or it will die. This morning I started it and now as soon as I give it some throttle it dies. Haven't had a chance to tear into it yet. I was hoping someone could give me and idea as where to start. Hoping that it's as simple as a fuel problem or something.