I don't know what the regulations are in NZ, but my reading indicates that in Australia, Regulation ADR 18 says speedos cannot indicate less that the true speed, and over-indication accuracy is limited to a maximum 10 per cent plus 4km/h. This means that at a true speed of 100 kilometres per hour the speedo can’t be displaying 99 or under, but it could be displaying up to 114.
That sort of variance could probably explain the discrepency in travel distance as well.
TC
|