Normsthename
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Should pull it OK if you lower the Gearing 
Andy
Andy
- Thread starter Gas mark 5
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ronan
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Should pull it OK if you lower the Gearing
Andy
Or shoehorn a BSA M21 600cc sidevalve engine into it and tell all the know-alls at bike shows it was a joint anglo-swiss-italian project ! That i'll confusticate them.
Gas mark 5
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Should pull it OK if you lower the Gearing
Andy
That's a good point actually, it will reach around 65mph in 4th gear without revving too highly, and 5th gear is more or less redundant (I am not a fast rider). Needs a new set of sprockets and chain anyway, so lowering gearing a little whilst I'm at it would be a good idea.
I've spent far too much time and money on rebuilding the duke engine now to stick something else in I'm afraid. In any case, if I were swapping the engine I think I'd put a Kubota diesel twin or triple in there, and maybe a turbo... Next time the duke engine destroys itself perhaps
.Although just the look on the anoraks faces would almost be worth the BSA engine in itself
.
Normsthename
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If it won't pull top gear standard then you will need to lower it quite a Bit.
I would look up the technical specs for the engine / Bike and put the figures into a Gearing Spreadsheet available on the 'Net
You can then tweak the figures so that it matches what speeds you are currently getting.
Adjust the final gearing (Gearbox and rear Sprocket) so Top gear is actually usable Solo.
I would then reduce the gearing a Bit more for the Chair
General rule of thumb is one tooth on the Gearbox sprocket equals two teeth on the rear sprocket.
Andy
