How to….. zero the Rally Roadbook Reader odometer

You will recall one of the pieces of advice about distance measurement on a rally is to measure your distance travelled from "waypoint of significance" to the next, zeroing the odometer at every important-looking waypoint, and that while your speedo odometer may be unhelpfully inaccurate, you can calibrate the Rally Roadbook Reader odometer.

Well here is how...

First calibration. See the three little lines, top right? Tap them...

You then get this:

Odo calibration +/- %. Set a course of known length, ride it and see how the numbers compare. Reset as appropriate and retest. Method of Limits, this process is called. You decide what level of accuracy to aim for.

As you ride the roadbook, you will see the odometer numbers, top left, top picture ticking upwards. We have already discussed the many sources of distance error. To distance-measure from waypoint to waypoint, zeroing the odo as you go, long tap to the left edge of the odo box. The distance number counts down to zero. Right edge to run the number up.

You could also adopt the technique of correcting your odo to the roadbook distance at every waypoint of significance. The end result will be the same....

See you in Gold River!