Curiously the inline-4 cylinder engine was being fitted into motorcycles very early in motorbike history. I say curiously because we like to think of technology as starting out with the simplest design and then evolving into more complex forms.

So although some early motorcycles were built using a single cylinder or horizontally opposed “boxer” twin, there were bikes being built in Europe and the United States with inline-4 cylinder engines right back around the turn of the twentieth century. The people who are generally credited with first putting into production a viable inline-4 cylinder motorcycle were Belgian firearms manufacturer Fabrique Nationale (FN).

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