'Motivator' runs!
Posted by : Andrew Freeborn - Date: 17 Jan 2003 at 14:31

Following a short and highly unlawful maiden voyage along the street outside the workshop (much to the amusement, nay, consternation of other residents) 'Motivator' first ran in earnest at the Aldo Scribante race circuit on 23 December 2002 .

The machine performed faultlessly, but it was soon realised that the spring/damper units fitted to the trainer wheel's suspension were too soft and had excessive travel. This gave a strange feel to the vehicle, making it difficult to get it up on to its main wheels and keep it there.

The Motivator and her crew at the Aldo Scribante Raceway in Port Elizabeth

The Bilstein shocks fitted to the front wheel suspension however worked well, although longer springs allowing a greater degree of pre-load will be necessary when running with the front end fully ballasted to give the correct axle load. The trainer wheel suspension was stiffened up and its travel reduced for the next session. This improved matters, but it still gave a soggy feeling to the machine when either of these wheels was in contact with the surface.

Finally the side suspension struts were removed entirely and the whole assembly bolted up solid with wheel height adjusted to allow about 13° roll either side of vertical. The pressures were reduced in the tyres of the trainer wheels to give a modicum of cushioning when the beast flops on to one or other side wheel and this improved matters considerably, giving a much more taught feel to the machine and improving feedback to the driver.

Some slight adjustments to the steering ratio and castor angle of the front wheel were tried. These were thought to improve 'driveability' although in truth it was probably driver ability that was improving with the increased experience gained over a total of about twenty-four 800 metre runs along the main straight. Efforts are now being made to secure the use of a runway at the local airport to permit further experience to be gained on a longer and considerably wider stretch of tarmac.

Our thanks are expressed to Luk Africa for the extended loan of their trailer during this period.