The recent document on Scribd which classifies bikes in terms of the number of wheels( see here) is not the first attempt to classify the various sub-types of these vehicles. For example, Archibald Sharp included a chapter on the topic in his book, “Bicycles and Tricycles” (ref. 953), which was published in 1895. The first level of his classification was based on the number of wheels:
…. Subsequent levels of Sharp’s classification included
- Front, rear steering
- Geared or ungeared
- Geared (chain, toothed wheel or clutch)
One fact which the extract from Sharp’s classification highlights is that three-wheeled and multi-wheeled bikes existed more than a hundred years ago. For example, there have been versions of quadricycles (4-wheeled bikes) since at least 1853, more than 150 years ago, see the following table:
Since a range of bike sizes and types have existed for over a hundred years, it would seem reasonable to expect modern highway design standards to quote dimensions and to design facilities for them.
983 Sharp, Archibald, “Bicycles and Tricycles – a classic treatise on their design and construction”, 1896, reprinted 2003 by Dover Publications Inc. New York, USA