[pneumatic]

All I am saying is that it isn't as simple as shown in that image. And it isn't. That is all I am saying.

The motorcycle examples are totally different because you don't have a main component anywhere that is supported by a single cantilevered bearing. The motorcycle clutch basket has the bearing inline with the teeth, but the image above of the PRE-Junker doesn't (as the clutch plate is shown inline with the teeth).

My original quote was "The not so pretty part is connecting the two cranks together to keep them in synch". And it was in regards to the following picture;



I was just saying that the picture above makes the engine look really really simple. But in reality you need to connect the cranks, which obviously makes the design bulkier. That is all I was saying. I didn't say it was hard to do, or couldn't be done.