Originally Posted by
Dylansbob
The only one I've seen in person had a single ring, are you sure the double is original?
If you look through the "On the Drops" blog page for the Lenton series (about 5/6 down the page, search for "Grand Prix No. 7" I think you'll find that in all of the years of production, the Grand Prix came with the same drivetrain description as 8-speed, including the Williams 46/49 crankset.
https://on-the-drops.blogspot.com/20...1948-1960.html