IIRC, and I rarely do, the Actia speedo takes engine rpms, trans gear, and tire size, to calculate speed and mileage. Not sure how Silverleaf does it; they may be reporting engine ECM speed data directly (engine has its own algorithm for speed, very similar to Actia's). Over time there is a small difference between Actia mileage & engine ECM mileage because the calculations are done separately.
My initial theory would be that the Actia calculation has snafu'd. Could also be there is a sensor going bad and that Actia takes the sensor data verbatim while engine does a check vs other data. Call Actia, Patrick Yuen, at 574-266-2649 for his opinion.
IIWMMy wife would make me slow down 20mph to correct the situation.
Baja-tested '08 2-slide 36'
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