A tall bike is an unusually tall bicycle often constructed by hobbyists from spare parts. Typically, two conventional bicycle frames are connected, by welding, brazing, or other means, one atop the other. The drive train is reconfigured to connect to the upper set of pedals, and the controls are moved to the upper handlebar area. Alternatively, a bicycle can be built by inverting the frame, and inserting the fork from the 'wrong side', flipping the rear wheel, and adding a long gooseneck and tall handlebars, then welding a long seatpost tube to the 'bottom' of the frame. This type of tall bike is made with only one bike frame, and is often called an upside-down bike rather than a tall bike, though the seat can be quite high, depending on the frame shape used. This type can be somewhat safer, as there is less tubing between the rider's legs and dismounting in a hurry can be easily accomplished. Finally, a tall bike frame can be made from scratch.
Practical uses
Tall bikes are usually used for recreation and entertainment, but can be used for general transportation also. Regular tall-bike commuters note that both their increased visibility and the simple 'wow factor' give them a safety advantage in automobile traffic over 'short bikes.' However, there are issues with mounting and dismounting similar to those presented by penny-farthings.
History
Historically, one of the first practical uses of the tall bike was as a late 19th-century lamp lighting system, by which a worker would mount a specialized tall bicycle while equipped with a torch for lighting gas lamps. As the worker rode to each lamp, they would lean against the lamp post, light the lamp, and then ride to the next. Upon completing the circuit of lamps, an assistant would help the rider dismount. The term 'lamplighter' is still sometimes used to refer to a very tall bicycle, for this reason.
Sporting
Tall bike jousting is a popular sport among tall bike owners, and is commonly considered to have been introduced by Jake Houle and Lil' Bob of the Hard Times/Black Label Bike Club. Combatants arm themselves with lances and attempt to score points by dislodging the other rider. Rules vary by area and with the mood of the combatants. Like all jousting games, participants consider it a sport in which honor plays a role and dishonorable wins are frowned upon. Jousters create lances that vary from simple PVC pipe and foam devices that are flexible, soft, and relatively safe, up to wooden or metal lances that may be quite dangerous. Regional rules vary, some specifying flaming lances for effect, or glass containers attached to the end, the goal being to break the glass container in order to score points.
Design considerations
Tall bikes present some interesting design considerations, and different localities tend to have different methods of dealing with them. One consistent issue is that the seat tends to end up in line with, or behind, the rear axle, which creates a powerful tendency to lift the front wheel of the bicycle on acceleration. Some bicycle builders simply accept this tendency, but others solve the problem by moving the seat post forward, lowering the handlebars, or by using a smaller wheel in front, typically a 24" instead of a 26". Stability can also be negatively affected, and enhancements such as extended wheelbase by welding extensions on the front and rear dropouts can benefit stability. Contest holders often place restrictions on such modification to prevent unfair advantages. See the bicycle and motorcycle geometry and bicycle and motorcycle dynamics articles for more on these issues.
