why????????

[plusinfinit]

So my bike is winterized by the book. I decide to get it out since it's going to be nice tomorow. I do evrithing by the book and i put new sparklugs in it. My bike starts up great but even after 6,7 minutes of running i can't rev it up past 4000 RPM. Whenever i rev it up i cuts out and dies. Sometimes i hear a poping noise , more like a metal knock. Why is that sound ??????? My bike runs fine, it stoped doing so but i am wondering why it made that noise.....? It a is suzuki bandit 600. Any advice would be great. Thanks.

[cjthor]

Drain out all the old gas and start fresh. Thats where I would start.