PD: Primary Drive Three-gear primary drive (Irving Vincent)

vinhrd998

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Anyone except Irving Vincent that have tried and hopefully succeeded well to build a three-gear primary drive?

Irving Vincent - Drive side.jpg
 

Peter Holmes

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I don't know the answer to your question, but I would be very interested to know how the ESA is constructed and works, and whether the ESA would be appropriate for a chain driven primary drive.
 

timetraveller

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If this is designed correctly then the shock absorber is built into the rear of the clutch where it interfaces to the large gear. This is the same idea which is used on some Japanese bikes where there are springs, the same idea as in a car clutch, where one set of springs takes up the forces in the drive direction and the other in the over run direction. This, in conjunction with a Bendix or pre-engaged starter motor in the original dynamo position, would be my direction of travel if I could get round to it.
 

greg brillus

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Several things to remember here......Ok all the engines the Horner's produce are for racing only.........they have a full CNC workshop at their disposal.........and all their parts are new, so not genuine cases and so on. There are very few of us that can approach this level of machining work, except for Vic that is........ For the rest of us, it is a challenge to come up with any of these ideas without destroying expensive parts in the process........They are great ideas non the less. The Horner's engines are visually a Vincent design, the rest is a different story. This is why they are not interested in producing a road bike as they are too different and no standard parts would be interchangeable. They have so many great features that most of us would love to have...........
 

vinhrd998

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Another picture with the clutch visible. Maybe you are correct timetraveller there is an integrated ESA in there?

Irving Vincent Drive and Timing sides.jpg
 

vinhrd998

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Greg, yes very non-standard. This picture showing how the shaft for the middle gear is fitted in the crank case.
Apparently Phil Vincent-Day, PCV’s grandson in the background.

Irving Vincent - Philip-and-the-winningest-modern-iteration-of-his-grandfathers-motorcycles.jpg
 
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timetraveller

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If anyone is unsure what one of the shock absorbers looks like here is a picture of one from a Suzuki clutch of the type ClevTrev was fitting several years ago. The plate on the right fits on top of the plate on the left. I have put one spring back in place to show how they fit. The plate on the right takes the clutch and the helical teeth on the left hand gear are driven directly from the engine main shaft.
P3280332.JPG
 
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Black Flash

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Well it is a race engine. I would not be surprised if this engine produces more transmission whine than a standard twin with all straight cut gears in there.
 
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