The image below shows short-stroke Norton crankshaft. This 80mm stroke crank is made by modifying a Triumph crankshaft. The stock Triumph spline is used for a Triumph drive gear (not supplied). If a belt drive is being purchased ask for a Triumph drive gear to go with your Norton clutch. Main bearings are ground at 30mm to match Norton main bearing sizes. This crank weighs about 5-1/2 pounds less than a stock Norton crank.
80mm Short-stroke Norton crankshaft: $1300 USD