10cc Glow Slide valve engine

[Basil]

Just acquired this gem to add to my collection. Very nicely built prototype. Just doing a strip down and clean before it gets parked on the shelf.

 

[Kosiba]

Is it a 4 stroke or 2 stroke?

 

[Basil]

Is it a 4 stroke or 2 stroke?

It is a 4 stroke. For many years I always thought the liner ports would need to seal against each other but the liner ports are sealed off by a piston ring on a static piston during the compression and power stroke. This static piston being part of the cylinder head. It really is an ingenious design unfortunately it does have its drawbacks. I love the simplicity though.

 

[Kosiba]

It is a 4 stroke. For many years I always thought the liner ports would need to seal against each other but the liner ports are sealed off by a piston ring on a static piston during the compression and power stroke. This static piston being part of the cylinder head. It really is an ingenious design unfortunately it does have its drawbacks. I love the simplicity though.

It looks pretty cool, I'd be curious as to how it'd sound! Does it sound like a 2 or 4 stroke?