Cannondaleriders

So to start out I don't have a lot of experience with my 02 cannibal. She sat for a while so I changed all of my fluids and the spark plug, the battery was dead so I had to jump it, she started up fine but as soon as I tried to give it gas she just died out then got a weird pop. She will sit and idle all day but as soon as I give it gas it will Rev up and down for minute then miss, give a pop out the exhaust and die. My dad was sitting there while I was screwing with it and said he saw it shoot a flame the last time it died. Any ideas as to where to start? I really want to ride but can not afford to throw parts at this thing hoping to fix it.

Check to see if both fuel injectors are firing. I'll bet one of them is clogged.

What's the best way to go about doing that?

The injectors squirt a small amount of fuel when you press the start button. You could remove them and test them connected to the fuel and the power. You would need to zip tie the injectors to the fuel lines or they will shoot across the room. The other way is to remove the airbox and try the test looking down the throttle body with a flashlight.

I would try removing the relay first. simple to try and doesen't cost anything. my cannibal did the same thing. removed the relay and it ran fine