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So to start the story off I just have to say that I wasn’t happy with the original carburetors and they were pretty damaged so I decided to get a little crafty and make a single carburetor conversion. Now This was a pretty interesting process but I think I got pretty lucky time wise. This only took me six hours to complete and I figured out the jetting pretty fast(Due to having a O2 sensor and a stockpile of spark plugs) So I have a Harley Davidson CV 40 made by keihin with a 48 Slow/idle jet, 165 Main jet And a few spacers for the needle. I’m getting good performance, good idle no fluctuations, Phenomenal throttle response, Amazing gas mileage (Surprisingly) And extremely fast cold starts (Warm starts are instantaneous)
Eventually I’m going to screw around with the manifold a little bit more so I can tuck the carburetor in a bit, But other than that everything has been working amazing. And I will have more updates soon!
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Just a sidenote nothing is currently on in these pictures. Everything is just resting in place because I am Currently maintenance in the carburetor (Diaphragm popped)
 

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VN 750 1994 RED/BLACK/SILVER
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Interesting experiment, perhaps the VN 750 will respond well to a single-carburettor conversion?.
The whole "V" twin engine motorcycle, is a new experience for me!

British twins were always made in single and twin carburettors versions, BSA, Triumph, Norton, Royal Enfield, in every case the single carburettors model was seen as the "Cooking" version and the twin-carburettored version the "Sports" machine, but that is as much marketing on paper as it is performance on the road. In every case, the latter machine would give you a better quarter of a mile figure and top-end speed, but on the road, economy, flexibility and smooth running, could be sacrificed. The golden rule for performance was an exhaust pipe and carburettor for each cylinder even in a multi-cylindered plot, aping racing machine were WOT performance is important. In real life riding the "cooking" versions, often out performed the tuned up versions on the twisted back roads of the English countryside, because of the "sweetness" of the engine's flexibity and the fact that multiple carburettors are difficult to balance and synch and get the engine in the right spot on, state of tune.. In real riding conditions flexibity, is what is needed over "balls-out"performance, as most of the time. Ike's are ridden at modest speeds.

Here in Britain, handling and flexibity was of vital importance, because of the nature of our roads, these days there are more and more dual carriageways and bland motorways, I once remember a South African rider telling me the first corner, nearest to him was 200 miles away!
Some multi-cylinder engines run, as four combined singles, BMC Mini are a good example of this from a tuning point of view. Where other multi- cylinder engines, run as true multi's. Engine characteristics is a fascinating topic, to me anyway! Best of luck, could the diaphragm, have blown out through differing engine internal pressures?
 
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