Project X900: hub-centre steering cracked?

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Hans Helms has been developing this bike for over two decades. Now, with plans to put the bike into production unrealised, its bright ideas are up for sale.

The majority of the patents are associated with the bike’s front end. Hub-centred steering has of course been tried before on bikes – but never with much success. Yamaha’s GTS1000 and Bimota’s Tesi both gave it a go.

Helms reckons he has cracked it with his design, at least in theory.

” The front end is based on the same design I used in the early 90s. That bike was tested by a German magazine and they were very impressed with it, ” he said.

Helms’ system works with a set of machined alloy brackets attached to the front and rear of the motor acting as mounting points for the front and rear swingarms, while thin steel tubes attached to the cylinder head support the headstock and seat unit.

Although the swingarms may look bulky, they are actually constructed of lightweight alloy.

The steering system works through a large alloy strut attached to the headstock. When the bars are turned this strut moves with the suspension along runners in an aluminium box fitted to the steering head. A Technoflex shock attached directly to the front swingarm and cylinder head provides the suspension.

Although at first glance the rear swingarm may look like a conventional single-sided unit a look at the right hand side of the bike reveals a horizontally mounted shock rather than the normal rising rate linkage. The precise design is another Helms patent.

It uses a tweaked Suzuki RF900R engine making 138bhp and it weights just 165kg (363lb).

Helms has opted for a belt-drive instead of chain. Since his firm – VH-Motorradtechnik – specialises in conversion kits to change other manufacturer’s bikes from chain to belt-drive, this is hardly surprising.

A huge 325mm single front disc provides the stopping power with a 240mm rear making up for any deficit the single disc looses over a twin set-up.

The fairing is made of carbon-fibre as is the tank and seat unit.

After 25 years of work… it’s almost complete.

MCN Staff

By MCN Staff