I installed the Vapor a couple weeks ago, and I can't seem to get the tach working correctly. When riding at a constant throttle, the RPM's jump all over the place (i.e. from 2300 to 6700 to 3600). I hit the rev limiter LONG before the shift light comes on, and it's set to come on at 7,000 RPM. I am grounded to one of the valve cover screws on the motor, and have the red wire wrapped 12 times around the spark plug wire (both of these were TrailTech recommendations). Has anyone been able to get the tach to work accurately, and if so, could you tell me what you did (like where you are grounded, # of wraps on the spark plug wire, etc)? Thanks.