All of us install lower gearing and larger tires. It would be tough to explore the backcountry and tougher trails if we didn't. Unless the ratio between tire size and lower gearing is the same as stock, we get speedometer error. While we can figure what the error is and do the math every time we look at the speedometer, it's a lot better to calibrate the speedometer to your new gearing and tire size.
Classic Instruments has made that a lot easier to do for those with electronic speedometers.
Classic’s new SN74 Module makes it easy to precisely calibrate most all electronic speedometers with just a touch of a button. The module wires in-line between the transmission’s pulse signal or ECM output and your speedometer head. The SN74 converts all known signals and includes an 8000 ppm signal output to control your electronic cruise control. Just push the button, drive a measured mile, push the button again. It’s that easy. The module mounts out of sight in any convenient location and the button switch is easily stashed behind your dash or removed after calibration is complete.
For more information call 800-575-0461 or online at www.classicinstruments.com.