Hi you can use this gearbox but to make it usable you will need to change your primary sprocket,a standard one as 20 teeth you will to change this to a 16 tooth and a 56 pitch chain .this should go straight on with out any machining of the gearbox shell to change the centres between the crank shaft and the main shaft.Then the final drive sprockets will need to be 13teeth on the front and 60 teeth for the rear.hope this will help.You can the the parts locally to you at Villiers Services in Quarry Bank .
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