Originally Posted by Doug5150

Tandem bicycles that have the riders sitting side-by-side are often called "sociables".
GIS: http://www.google.com/images?hl=en&e...w=2112&bih=967

The old-style sociable upright bicycles are copied by homebuilders, but haven't been commercially manufactured in many years. Any factory-made one you find still usable is Copake bait.

Most of them now are two bicycles of one kind or another that are linked side-by-side somehow. The main problem with them is that they tend to be considerably wider than two bicycles, so there's not much places they can be easily used.

The problem with any four-wheel configuration.... is that it's one more wheel than you really need. There used to be a recumbent trike company that made a special-order sociable trike, but I cannot find it now. You could ask in the recumbents forum, or on bentrider.online.

Atomiczombie has plans for a sociable delta recumbent trike called the Kyoto Cruiser.
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