Holder GmbH Grunbach R1

The air-cooled single-cylinder engine of 153 cc runs on a petrol mixture and delivers 3.2 hp at 3,300 rpm. Instead of wheels, the machine runs on a track, through which it transferred power to the ground.

A track in place of wheels gives a small machine like this better grip and lower ground pressure on soft or rising terrain, where wheels would easily lose traction. An air-cooled engine this small, running on a petrol mixture, was built for the smallest, intensively worked plots, such as terraced land, gardens or hillside plots, not for open fields.

When buying such a rare machine, the condition of the track undercarriage with its rollers and track links matters most, since wear here is judged differently from a wheeled vehicle. Equally important are the compression and ignition of the small two-stroke engine and corrosion on the sheet-metal parts. Since only 50 units were ever built in total, spare parts are now practically unobtainable; what matters most here is how complete and original the individual machine is, right down to its original track links and rollers.