Lumley Engineeting - Hub Centric Steering System to Give Smooth Performance on Tour for Osmington
This customer has owned his BMW K1000 for a good few years now and it has served him well, hauling a sidecar around European and British roads for thousands of miles.
However, there comes a time when the shortcomings of the standard setup with a sidecar attached get just too much to bear; the steering feels heavy and unresponsive while the outift isn't stable, which is uncomfortable for passengers and the rider too. Also, even when touring, the idea of getting through the corners faster and more smoothly is always an attraction.
With this in mind, Dan brought his trusty BMW down to our workshop for the full hub centric treatment. Fitting the new sidecar was a very simple matter, instantly changing the appearance of the outfit with its swoopy lines inspired by 1950s F1 cars. The unique wishbone suspension on the chair is controlled by a bespoke unit from the Shock Factory, calculated to perfectly match the weight of the machine and the anticipated loading.
The sidecar mounts also support the front suspension members, which curve around the front wheel to allow steering movement, provided by the two rose jointed actuation rods fitted to the top of the suspension upright. The upright is the heart of the hub-centric system and is massively strong to make sure that the wheel travel is vertical, using car type ball joints top and bottom. The movement is controlled by another custom made Shock Factory unit with adjustment for pre-load, ride height, bump and rebound damping to fine tune for the prevailing conditions.
Stopping power is provided all round by Willwood radial calipers gripping Vauxhall discs, and the wide wheels give great grip to let them do their work without drama.
Dan is due to collect the finished machine soon and we can't wait to hear his reports of the next tour. Who knows? He may even bring us back a bottle of duty-free something nice?