Spagthorpe Motorcycles

Spagthorpe Research
G1200
The concept of the lateral-crank boxer twin was abandoned after the Spagthorpe G1200, which was a fore-and-aft opposed twin. It used a single-thow crank, which had the unfortunate effect of tremendous primary oscillations when those big 600cc pistons whumped fore-and-aft. The front cylinder would breathe excessive intake charge because of the acceleration that happened as the pistons moved back and the bike was thrown forward, and the back one would suffer (also because of its position right in front of the back wheel, it would suck rocks. This was before air filters were invented.) The vertical opposed-twin was another Spagthorpe proposal, but it never made it onto the drawing boards because the design was too tall, and portrait-mode drafting paper hadn't been invented yet.
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