Not a V-twin..courage single sv590 just like on my cub,
I remember I asked Kohler out of curiosity for the max speed awhile back, it's 3400 or 3450 RPM...
Usually if something is wrong with the mechanical governor you have no throttle control or the engine runs Wide open fast as possible...
MY uneducated guess may be a weak or stretched(maybe cracked) governor spring.... We'll see what the experts say and we may both learn sumthin. Also is your choke opening all the way? you can see by removing the air filter cover and filter and you'll see the choke butterfly in the opening lower left corner.