The Modular Bike

"Modular: constructed with standardized unit or dimensions allowed flexibility and variety in use; modular furniture: modular homes"

A few years ago, I built an adaptable tandem bike from 2 abandoned Malvern Star folding bikes. It was made with an "insert" between the 2 halves of a folding bike. The bike was good, but I started thinking of the possibilities of something better or different. My modular bikes are the end result. The bikes are designed from the ground up to be assembled as tandems, recumbents & load carrying bikes and the aim is to make these specialist bicycles affordable by using a cost-effective modular construction.

The design is patented and this article was featured in the Jan. 2005 issue of Velovision. (to find the patent, go to http://apa.hpa.com.au:8080/ipapa/qsearch and search for modular bicycle to find the patent documents. Pick the top entry you find.)

This construction includes standard frame units with extras, like a suspended rear triangle, steering link, rack, trailer and recumbent seat & boom. The frame has attachment points at the ends for holding another frame or extras, a tube that acts as a static handlebar mount, and tubes that can support pulleys for a front-wheel drive mechanism. The seatpost doubles as a mount for the recumbent seat, as do the bottle mount bosses on the top tubes.

I have taken care to ensure that the extra features on the bike don’t look scrappy when unused – for example a plastic plate can fit over the front attachment points. So far there have been 3 designs of the modular bike and I have designed a set of models of the bike which you can make for yourself at home.

The thumbnails all show a bike type and most link to their own webpage.

Standard Bike with Rack

Underseat Steer Short Wheelbase Recumbent

Models of the Modular Bike

Hybrid Tandem Front Steer

Hybrid Tandem Rear Steer: In Canberra & Racing at Broadford

Tandem Rear Steer

Back To Back Tandem

Long Wheelbase Recumbent

Load Carrying Options: Tray on Tandem,

Front Storage Tub

Trailer

 

As well as the bikes shown, you can build conventional tandems and triples / hybrid triples from the modular parts.

The latest bike design uses NC routing, laser-cutting, steel tubes & flats, plastics and timber seats. These are all processes and materials I’m comfortable with in my job as a mechanical engineer. Mark 4 will probably use investment cast lugs and lighter, thinner tubes. Maybe by Mark 7 the frame will be moulded from a single piece of carbon-nanotube reinforced plastic!

Below are pictures from patents that were cited as "related art" in my patent assessment: left to right we have patents RU2063355, FR2422545 and SU1335495. The modular bike concept shown in SU1335495 has been taken up by Bike Friday (Q models) and Santana have a similar modular bike. Hase trikes can link to form a tandem.