The Six Stroke Engine

Sir Alan Cathcart

Early version with four carbs

Centre Carb - 3 Carb Version

The 35mm CV on the left supplies both cylinders via a very long 28mm manifold, and is adjusted via the cables to open with a small throttle movement, its arm being slightly longer than the other two carbs. These other two 35mm CV carbs supply each cylinder via short 35mm manifolds.

Malcolm with working 6 stroke model

Top End

Looking down on top of the head the scotch yoke and upper portion of the piston are visible, with the crank webs beneath. When the small hole in the centre lines up with the oil hole in the centre of the sliding block, the engine is at TDC.

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Disc Valve - Front

The piston is half way up on the exhaust stroke. When the piston reaches TDC with the ports fully open, the disk will begin to cut off the exhaust. The valve runs clockwise.

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