https://www.enginela...onnecting-rods/
Recently, we posted this engine on our Facebook page for Weird Engine Wednesday. While our plan was to use that as a teaser for this Throwback Thursday article, several of our more adept fans found the article on their own and posted it in the comments. This engine is so interesting, it’s definitely worth the repost.
Starting with a Honda based four-cylinder engine, Dieter Hartmann-Wirthwein patented a system in which four cylinders operate using only one single connecting rod.
Essentially, the two center pistons are connected via a “Y” shaped connecting rod. Also attached to those center pistons is a pivoting mechanism that is attached to the two outer pistons. This unique arrangement allows all four pistons to work as a single mechanical assembly, which transmits power to the crankshaft via a single connecting rod on a single crankpin.