Radrob,
that's what one would call a tandem-twin. In a typical two stroke engine design the piston moves down during power stroke, the fuel mixture in the engine casing compresses. By the time the piston crown reaches the transfer ports the compressed fuel mixture then flows into the sleeve to be compressed further by the piston on it's return stroke just before the spark plug ignites the fuel mixture. An inline two cylinder two stroke needs some kind of partition to isolate each piston (depends on the firing order and design, that's why most 2cylinder 2stroke designs have it that both pistons move up and down together) so that the gasses does not flow to areas it should not. A tandem twin is just an alternative way of engineering this needed "partition"......
Cabinfever1977,
At some stage the big players in the rally world (Renault & Volkswagen) tried the approach of two engines in one vehicle. One engine driving the rear wheels and one engine driving the front wheels. The engineers discovered that in a situation where every wee bit of power matters that syncronising the two engines is nearly impossible..... thus the idea was moth balled by both manufacturers. The only way to achieve good "tuning' is to share the fuel (induction) supply to the pistons, thus in the end one can just go through the effort by increasing the displacement of the engine, it is much simpler and cheaper....
You Americans have a saying: "there's no substitute for cubic inches".....
