Do you know {that a} sq. 4 engine was a factor? In reality, early designs date again practically 100 years to a person named Edward Turner. He was a motorbike designer within the UK who penned up a compact engine that basically fused two small twin cylinders right into a single four-pot. He offered the design to an organization referred to as Aerial Motors, and thus the Aerial Sq. 4 was born.

One would not merely stick a few inline twins collectively for a four-banger. As this video from the YouTube channel Driving 4 Solutions demonstrates, this engine is really a sq. form with the cylinders pointing straight all the way down to the crankshafts. Sure, that is crankshafts—the design makes use of two counter-rotating crankshafts linked with geared flywheels. The cranks path one another by 180 levels, and the pistons are diagonally matched. This ends in a firing order an identical to an inline-four.

With out getting too technical, this all results in an engine that is inherently well-balanced and smooth-running. Based mostly on the video, it would not sound unhealthy both. And the sq. design makes it supremely compact, basically taking on the identical area usually occupied by a V-twin or perhaps a large single-cylinder mill.

The sq. 4 engine wasn’t only a flash within the pan. Aerial Motors constructed the Sq. 4 bike for practically 30 years, and sq. 4 engines have been additionally utilized by a couple of different bike producers. It made good low-end energy, however it was an costly engine for the time, and it suffered from overheating points.

There was additionally treasured little room to have a thriving consumption system to feed the engine, which was high quality so long as the powerband stayed low within the rev vary. However as bike know-how advanced to small, high-RPM engines, the low-speed sq. 4 simply could not sustain. Aerial ended manufacturing of the Sq. 4 in 1959.

The video notes that know-how has advanced to the purpose the place a sq. 4 might thrive. However with the world slowly shifting in direction of electrical energy, that is probably an engine design that can exist solely within the historical past books.