Gutless 2002 Prairie. Why?

[idahorider]

So I am hoping that many of you more experienced riders/mechanics can help me out with a problem that I have been having with my 2002 kawasaki prairie. Just a little background first. I received this atv from my father in exchange for some work. It has been a great atv with plenty of power. It has been used mostly on the farm and has just over 2000 hours on it (2024). My father stopped using it for about two years. It sat inside his shop for this whole time. He claimed that it didnt run very well and isnt the type to go get it fixed so it just sat with a 1/2 tank of gas in it for over two years. This is where the problems began. I got on it and drove it and immediately noticed that it was gutless. Slow throttle response, little power and would only go about 15-23 mph. I figured since it had sat for two years the carb was gummed up and needed to be cleaned. So I cleaned it. Put it back together and still no luck. Talked to some friends they said clean it better. So I cleaned it in some of the nastiest carb cleaner that I could find. Blew out all of the ports and needles and got it looking awesome! Still was gutless. So I read forum after forum looking for similar problems and applied all that I could. I thought that is was the belt switch so I flipped it and actually put it in the "slow mode". Screen on the meter was flashing and everything. Flipped it back and the screen was normal again but still gutless. This is when I realized that I didnt put fresh fuel in (I know...stupid, but learning). So I put new fuel in and still gutless. I thought that it was the fuel filter. Realized that there was no inline fuel filter so I pulled the tank and removed the fuel pump and cleaned the filter that is in front of the fuel pump. Put back together and still gutless. Then I realized that I had been running the "cleaned" carb with the old gas and maybe thought it had gummed it up again. So I deep cleaned the carb again. So with clean gas, cleaned fuel pump filter, switch on the belt cover in the correct position and a very clean carb I still have a gutless atv. I am seriously at my wits end! Sorry for the long post but is there something that I am missing? Please lend me some advice. Thanks

[sorunuts2]

Not sure if you still have the problem, I will offer a couple suggestions anyway. So as for aspiration, is the air filter plugged? Mice have been know to build nests in exhausts. When you start is there long cranking, idle fine, act like it runs down in power or is the problem cotinuous? Use this to determine weather fuel supple problem or not.

What color is the burn on the plug? I would expect it to be lite gray to very lite brown being a 4 stroke. Black powder indicates over fueling, shinny black indicates oil/ weak rings (compression and leak down test). What color is the spark? The more yellow the weaker the spark. This would cause long cranking and misfires. Well hope I could give something helpful for you.

I do like to ride in Santa Idaho area.