The tandem bicycle or twin is a form of bicycle (occasionally, a tricycle) designed to be powered by more than one person. Originally tandems were built by welding two bicycle frames together to form a two-person bicycle. Modern technology has improved component and frame designs, and many tandems are as well-built as modern high-end road and off-road bikes. Due to the additional stresses caused by multiple riders and higher weight, tandems typically require stronger components than ordinary bicycles.
A traditional
tandem bicycle
A tandem recumbent bicycle
While a tandem has double the pedalling power with only slightly more frictional loss in the drivetrain, it has about the same wind resistance as a single bike. High performance tandems may weigh less than twice as much as a single bike, so the power to weight ratio can be similar to that of a single bike and rider. Tandems can reach relatively high speeds, especially downhill and on flat to rolling terrain. They are not necessarily slower on climbs, but are perceived as such, in part due the need for a high level of coordination between the riders, especially if the physical abilities of the two riders are very different, requiring compromises in cadence or effort level.
On conventional tandems, the front rider steers the bicycle and is known as the captain, pilot, or steersman; the rear rider is the stoker, navigator, or rear admiral. On most tandems the two sets of cranks are mechanically linked by a "timing chain" and turn at the same rate; some designs such as the DaVinci allow independent pedaling through the use of multiple freewheels. The Opus Counterpoint is an example of a tandem steered by the rear rider who sits upright while the front rider rides in a recumbent position.
Tandems are also available as tricycles; the conventional tandem trike has a small but devoted following in the United Kingdom, and is available in one-wheel and two-wheel drive designs. Recumbent tandem tricycles are also gaining popularity throughout the world.
The Goodies on their 'trandem'
Tandems can have more than 2 riders — tandem refers to the arrangement of the riders one behind the other rather than the number of riders. Bicycles for three, four, or five riders are referred to as "triples" or "triplets", "quads" or "quadruplets", and "quints" or "quintuplets" respectively. One such familiar to UK TV viewers was the "trandem" ridden by The Goodies, originally a 2-man tandem with an extra "dummy" seat attached, a full 3-man version was built for them by Raleigh. A famous ten-person bicycle or "decemtuplet", the "Oriten", was built in 1896 by the Orient Cycle Company. Perhaps the longest bicycle ever built was the Seventy four-seater built in 1984 in Queanbeyan, Australia.
Tandem bicycles are often used in competitions such as the Paralympics with blind and visually impaired cyclists riding as stokers with fully-sighted captains.
External links
- Atomic Zombie Extreme Machines - do-it-yourself books, plans, forums and gallery
- The Tandem Club — a UK-based club
- The Tandem Club of America — an originally U.S.-based, international club
- Ten person bicycle (image of) — View the picture of ten-person bicycle.
Categories: Cycle types | Cycling
