Has a BMX bike ever been transformed for touring?
A good example of using 20&quot; wheels for a serious bicycle is the Moulton.
Although there is nothing of a BMX bike except the 20 inch wheels.
The problem with using a BMX frame is that it is sized very small. This makes it difficult for a rider to find an efficient riding position for long rides.
The points about the smaller wheels benefits in the question are exactly why Alex chose that size wheel for his design.

In the late 1950s, disillusioned with the design of the classic bicycle, Alex Moulton set about creating a new design. He thought the classic diamond frame was inconvenient to mount, difficult to adjust for size and not suitable for both sexes, and that 'Ladies' open frame bicycles without the top tube of the diamond frame were structurally compromised for ease of use. He believed that classic bicycles (especially with small frames and smaller wheels known as 'shopper' bicycles) were uncomfortable to ride without the use of wide, low-pressure tyres which increased rolling resistance. He also thought large wheels made a bicycle slow and cumbersome to store, and did not easily fit emerging societal commuting patterns in the developed world, which often combined more than one form of transport.
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