-JdK- Viktor made this drawing to reproduce a tank for his Model 18 Norton. He took the measurements from two original 1927 petrol tanks that differ slightly in dimensions. The original tanks were produced by TLC while the frames were produced at the Norton works. My guess is that the dimensions of both tanks and frames varied slightly and that matching pairs of tanks and frames were selected for a proper fit. A proper tank fits snugly in the frame without too many airgaps. Therefore these measurements should be taken as a guideline; adjust the sizes when required by a somewhat taller or smaller frame.
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