If the horsepower output is only restricted by the CDI box, then there's hope. I have modified a few ATVs in my time, and there are a lot of aftermarket companies out there making customizable CDI boxes, and generic ones too. Jetting the Carbs, and letting the motor breathe seems to net huge results as well. 16hp seemed VERY conservative for a 570cc V-Twin to me. If this was a Honda engine, we would probably be looking at more like 35hp out of the same displacement.
I have been eyeing the Kawasaki Mule for a few years for the same reason that the Gator is so appealing now. However, after a lot of investigating I have found that the differentials are geared too low. Spinning the drive line up any faster would only net disaster in a short time. There is no speeding up the Mule without replacing the entire powertrain.
Does anybody know if there are any other restrictions in place other than the Governor built into the CDI on this Gator. I have seen models that have restrictors in the exhaust, and the intake. I have seen restrictor rings on the CVT to keep the speeds down. I have also seen various combinations of all of the restrictions.
I'm not looking for raw power here. I just don't want to be the annoying guy in the bunch if I decide to go riding with the Rhino boys one day. At 35Mph, I'll be brining up the rear. AT 28, I'll be the guy that they have to keep waiting for at the turn offs.
If I could squeeze an extra 10mph out in short bursts then I'm in!