My lt 250r seems to be sluggish. I noticed when I am lighter on the throttle it accelerates better. The carb is slightly larger than stock with a k&N. Is this carb too big for the motor? How do I know if the jetting needs adjusting? Is there a recipe for power when it comes to setting up the carb size, jetting, etc.? This machine is an 1985 and has no key can I put a key switch from a 1987 on it ok? I am running 32:1 FYI.