Belmog and Halda
In the sixties serious competitors in rallying used mechanical trip meters to improve their navigation and finish higher up the finishing order, of which the Halda Twinmaster was the most popular. Like almost everything else mechanical, Haldas have since been superseded by equivalent electronic gizmos.
However, classic regularity road rally's organised under the FIVA and FIA regulations allow only mechanical rally instruments to be used, and as Haldas are no longer being made, a new modern mechanical trip meter called the Belmogtwin Mk II has been developed which has all the important functions needed to navigate your way to rallying success.
For regularity rallies, two counters are always needed. One counter is used for the intermediate distance to calculate the distance between road instructions, the second counter is needed to calculate your average speed over an indicated section. The instructions can be given in the roadbook by a lot of different indications. Some organisers do not hesitate to let you go twice around the same roundabout and it is, therefore, necessary to have a distance counter which can give you the exact distance up to 10 yards or metres. This is possible with the Belmogtwin which can be calibrated to every car by changing the calibration cogwheels, the same procedure as with the 'old historic' rally instruments. It is very important to have the Belmogtwin in time to calibrate it and do some 'training' runs. People who are starting their first rally are very often disappointed just because they make mistakes caused by last moment 'hectic' preparations.
Rally trip meters are delicate instruments, very often used in aggressive conditions. Temperatures on the dashboard of a car can vary from -15 °C to +70 °C, not forgetting the unbelievable vibrations and shocks in a car. Fortunately, the Belmogtwin has been developed by an experienced rally competitor and has been well proven to be a winner in such conditions.