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Explain xkcd: It's 'cause you're dumb.
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Timeline of Bicycle Design
I'll be honest--the 1950s were a rough time for cycling.
Title text: I'll be honest--the 1950s were a rough time for cycling.


Ambox notice.png This explanation may be incomplete or incorrect: There still isn't much here. We could use a table of each bike design and what's wrong with it.

Randall created a 200 year history for bicycles with 13 designs ranging from 1810 to 2016. Most of these bike designs are completely fictitious. [citation needed]

The only model that both looks like a real model and fits the year is the 1875 model, which resembles the Penny-farthing. The Penny-farthing was popular in the 1870s until the Safety bicycle took over around 1880. The 1875 model appears to be missing handlebars, but it's worth noting that on the real bicycle, the handlebars were very small and close to the saddle, and may be too small to appear in the drawing.

The 1860 model looks like the American Star Bicycle, but that bicycle was first invented in the 1880s.

Some of the other examples of "bikes" could, however, look like those in the image at the top of the Velocipede Wikipedia page.

Several of the "bikes" are shown with a human — Ponytail is "riding" the pole-vaulting bike, Cueball appears in four designs, and Megan appears in three. These humans provide a sense of scale and, in some cases, a demonstration of how the bike might be operated. Megan's appearance in the 1900 design shows how huge that bike is, appearing to dwarf the previous two models while continuing the short trend of ever-increasing size.

Only two of the bikes have pedals (1875 and 2016) and only one has a sprocket with a chain (1980). Seven designs include a seat for the rider — eight if you count the device holding Megan in the 1980 model.

The 1925 model is reminiscent of a fractal; Benoit Mandelbrot was born in October 1924.

The 1880 model could be the result of an evolutionary algorithm trying to produce a bicycle. Some sub-optimal algorithms that have been given the task of creating a vehicle have been shown to misplace parts in ways that makes them completely useless and/or inaccessible — for example, placing a small wheel inside a much larger wheel.

This comic (especially the 2016 bicycle) is possibly also a reference to The Science of Cycology, a cognitive psychology project run by Rebecca Lawson at the University of Liverpool, which asked study participants to draw a bicycle from memory. The error rate was high, supporting a hypothesis that humans over-estimate their ability to explain how things work. Gianluca Gimini ran a similar project, Velocipedia, in which he asked people to draw free-hand sketches of bicycles from memory, then later rendered some of the results as if they were real bikes.

Also, the designs given for the years from 1825 to 1925 distinctly resemble designs that tend to evolve in the various challenge environments in the genetic evolution games BoxCar2D (Flash Player) or Genetic Cars 2 (HTML5).

The 1980 design looks strikingly similar to the southpark "wild whacky action bike".

The title text refers to the scene labeled "1955" which depicts Cueball being chased by 3 bicycle wheels. Whatever caused the wheels to chase Cueball down a hill is left to the reader's imagination. It could be that the wheels have become sentient and are actively chasing Cueball, or it could be that the bicycle failed horribly and Cueball is running from the wreckage. The era this "bike design" is from (1955, which is in the 50s) would be hard to ride a bike in if it was the only available design.


[13 drawings 8 in the top and 5 in the bottom row of different and weird "bicycle" designs. Above them there is a heading, and below each bike a year is given. On the very last cycle there is a drinking bottle with a label.]
Timeline of Bicycle Design
[Ponytail hanging on to a bending rod that goes down to a single normal sized bike wheel. It looks like a unicycle with no seat. The rod is bending quite a lot so she looks like she is about to use the contraption as a pole vault]
[Cueball is running after a device holding on to a rod bend in several places before reaching the ground at a very small wheel that then is connected with a shorter rod to a normal sized bike wheel.]
[Two normal sized bike wheels connected with a single rod between them.]
[Megan sits on a large saddle on top of a double sized bike wheel, she has some kind of handle bars to hold on to (or it could just be the saddle) and then a small rod goes down to a half size front wheel.]
[A regular drawing of a Penny-farthing with very small back wheel (half the size of the front wheel on the 1860 bike) and very large front wheel (larger than the 1860 bike) and pedals in the middle of the front wheel. The handle bars on such a bike is so small that it is likely they cannot be seen in this drawing.]
[A huge wheel twice the size of the one on the Penny-farthing, and then a small wheel (like the small one on the Penny-farthing) hangs in a rod from the center of the giant wheel. The small wheel has a saddle attached, but it is not straight up.]
[This is the largest bike. Not the largest drawings, but where the other have the characters in roughly the same size, this one has a small drawing of Cueball standing on top of the wheel holding on to some kind of handle bar. The wheel is about three time his height.]
[Cueball sits in the "saddle" of a bike design that is similar to the Penny-farthing, but the saddle is more a rod, and the back wheel is on a rod going straight down from where the saddle ends. Also there are no pedals, so Cueball seems to be directly spinning the front wheel by hand.]
[A symmetrical saddle sits on top of single bike wheel, as with a unicycle but no pedals, but then there are (at least) six progressively smaller wheels in-line to the first, three to front and three to the rear, each new wheel approximately half the size of the one before. A possible fourth wheel, presumed to complete the set of medial stabilisers, can no longer be discerned from the rod that goes through the center of the larger wheels.]
[Megan stands on top of a saddle with a oar that looks like the single-oar sculling used for gondolas in Venice. She holds this to the ground behind her, while trying to move her bike forward. The bike consists of four small wheels, one straight under her, one behind, one equally in front of her and the last even further in front. They are all connected to the saddle with individual rods.]
[Three normal sized bike wheels are rolling down a hill after Cueball who runs away from them with his arms up.]
[Megan sits on a bike contraption that seems to have a holder around her mid section rather than her sitting on a saddle. This holder goes to the back wheel below her, and there is actually a sprocket with a chain, although no clear pedals beneath her feet. She holds on to a very long handle bar, which connects with two long rods coming from the sprocket at the front end of the bike far ahead of Megan, below which is a wheel, to where the chain is actually going. Both wheels seems to be normal size.]
[Another weird contraption of a bike with pedals on both normal sized wheels which have handlebars on the side pointing down towards the front. The saddle hangs in a swing, connected to a rod above it, which goes to the front of the bike and splits in two rods which connect to the center frame of the bike. In front of these there is a contraption resembling many styles of touring bike handlebars, which sits just above the front wheel. The two wheels are connected with a long rod between the center of the wheels and in the middle of this is the center part of the frame going up toward the handle. On the middle of this is a bottle with a label. Towards the back wheel there are two rods sticking out, one presumably a kickstand, the other possibly a parking brake.]
Bottle: Milk

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