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Dashport Nut
- Thread starter Rick G
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Roger
Luke Skywalker
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A little SU history .
The very first worked on the same constant depression basis, but instead of a piston in a dashpot regulating depression, had a leather bellows. This was in keeping with the SU name - Skinner's Union.
Later gravity side-draft SUs had a solid (heavy) piston in a dashpot, with no spring and no damper. The Dashpot isn't the damper - the damper is the little rod with its own valved piston on the end that fits inside the hollow upper stem of the big piston. Those without dampers suffered from flutter, so even later carbs had solid pistons but with dampers.
Later still they developed light-weight hollow pistons with dampers and springs of various grades to control the rise and fall of the piston more accurately. These were much better in the popular semi-downdraft applications common in the 50s and 60s.
That's without going into details of Downdraft and Sloper carbs, which are another kettle of fish entirely.
The very first worked on the same constant depression basis, but instead of a piston in a dashpot regulating depression, had a leather bellows. This was in keeping with the SU name - Skinner's Union.
Later gravity side-draft SUs had a solid (heavy) piston in a dashpot, with no spring and no damper. The Dashpot isn't the damper - the damper is the little rod with its own valved piston on the end that fits inside the hollow upper stem of the big piston. Those without dampers suffered from flutter, so even later carbs had solid pistons but with dampers.
Later still they developed light-weight hollow pistons with dampers and springs of various grades to control the rise and fall of the piston more accurately. These were much better in the popular semi-downdraft applications common in the 50s and 60s.
That's without going into details of Downdraft and Sloper carbs, which are another kettle of fish entirely.