Quoth Alan Weeks:
I regularly ride two bikes that were considered lightweights by the manufacturer when they were built in the mid-1940s though I question whether the first generation of Schwinn Continental is considered "on topic" here.
The classic definition of "lighweight" was anything with a tire size narrower than 1 1/2".
My next internal hub project is to use an AW with two cogs on an early '60's Viking. I have yet to try fitting the hub in place but I'm thinking that the Viking's Cyclo-Benelux derailleur should handle the two cogs.
Maybe not. The old coil spring Cyclo Beneluces were sized for different width clusters. Yours may have too much travel, which would put it at risk of shifting into the spokes.
The cage is typically marked with what freewheels it is intended for, such as 5 x 3/32 , 4 x 3/32/3 x 1/8, etc...
Sheldon "Mark VII" Brown
Las Vegas, Nevada