SQUARE FOUR ENGINE.

[Longboy]

A pair of 180deg crank twins combine together on a centralized flywheel shaft for a rare configuration engine, the Square Four. From LONGBOY ENGINE.

 

[RonGinger]

Thats cool. And what a strange sound. At first it sounds like a rock crusher, then you get to hear the beat.

I dont quite see how the intake valve works. Is it in a manifold off the side of the head?

 

[vk7krj]

Nice one Longboy- kinda reminds me of the old pommie motorbike, the Ariel Square Four. As I remember it, it came in 2 sizes, 600cc and 1000cc and was a good touring engine, but never a performance machine. Had a really nice exhaust note.
https://en.wikipedia.org/wiki/Ariel_Square_Four

 

[Longboy]

Thats cool. And what a strange sound. At first it sounds like a rock crusher, then you get to hear the beat.

I dont quite see how the intake valve works. Is it in a manifold off the side of the head?

Yes, atmospheric valve blocks between the two cyl. banks. You can view the build log here in the Photos and Videos forum.

 

[Longboy]

Nice one Longboy- kinda reminds me of the old pommie motorbike, the Ariel Square Four. As I remember it, it came in 2 sizes, 600cc and 1000cc and was a good touring engine, but never a performance machine. Had a really nice exhaust note.
https://en.wikipedia.org/wiki/Ariel_Square_Four

See my introduction in the build log here! LONGBOY'S "SQUARE FOUR" MODEL GAS ENGINE.