Since 1 mile equals 1.6 km, a simple gearbox providing the conversion is all that is needed. This is what Motrax have built.

The Speedo and Odo are linked together ( to be clever about it, acceleration is differentiated to give speed, and differentiated again to provide distance. It's a maths thing...)

Therefor, the converter will convert the whole instrument to MPH, including the odometer. To be truly accurate, you should calculate you KM reading in miles, and reset your odometer, or it'll be wildly OTT!
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