Speedometer Calibration

1. Remove the original driven gear.
Ts = Number of teeth on service driven gear
To = Number of teeth on original driven gear
Va = Actual vehicle speed
Vi = Indicated vehicle speed
VSS = Vehicle speed sensor

NOTE: Design accuracy is: -3/+8 km/h at 50 km/h and 100 km/h (-21+5 mph at 30 mph and 60 mph).

2. With Va, Vi, and To known, calculate new number of driven gear teeth.
^ Ts = (Vi x To)/Va.
^ Ts = (To x new tire revolutions per mile)/(old tire revolutions per mile).

NOTE: Use one of the formulas.

3. Round to whole number, dropping fractions less than 0.6, and rounding up if fraction is 0.6 or higher.