Had more time to think about this one, and have some more "maybes".
Check the spark plug gaps. Make both as nearly the same as possible. Sounds crazy I know, but there's something about the Kawasaki twins that makes them very finicky about this.
Next, check the valve lash and put them right on the money. The possibility of a bent push rod might be of concern too, but the only bent ones I've found were caused by the rod falling out because of loose rocker to valve lash clearance. At least that's what I thought at the time, since the other side was way wide. It did run with no strange noise, but the exhaust sounded funny. A bit low on power but not as much as having a dead cylinder. Could a backfire cause a bent push rod? I don't know. They have a very delicate appearance.
I have wondered if the occasional "back fire" could break or begin the demise of the plastic gears. The occasional "running on or dieseling" is another concern, but I can't back that up with hard evidence.
Sorry to ramble, but hope you will check out these suggestions before doing a cam job. That is a low hour machine, but the cam might be the problem.
Keep us posted, as this subject will come up many more times in the future. I suspect we will learn some bad effects with the steel geared cam sooner or later.
tommyhawk