I have a 2003 Softail Springer stock. My tachometer started bouncing a few days ago. I went for a ride today same thing its bouncing but never goes to zero rpm's. It's running smooth no missing nothing smooth as can be. Could the tach it self be bad it bounces when getting up to speed it'll bounce on and off and while just cruising at 60mph. Bike has 14,500 miles on it. Any advice is greatly appreciated. Thanks