Do you have any idea what size chain would be on a 1970 Max II?
If the vehicle has an original engine that was 340cc or smaller, the long final drive chains are #40, 125 pitches. If it has a larger engine, RI would have used #50 chains on the final drives, 102 pitches. The short chains coming off the jack-shafts are a mix of #50 (46 pitch) and #60 – #60 is the vertical chain. The number of links on the #60 chain varied – RI had various sprocket/gearing options back then.