I did a club ride today 1/2 Century (50.4 mi actually) and averaged 18.4 mph.
High was 29.2, and did a lot at 20 - 22. Can't hold anything above 22 in a pace line for more than 20 mi.
This old 1948 2 cylinder engine just ain't got the carburetion to keep up with the newer models.
In So. Fla. we don't do much climbing hence not much downhill. Did some great rides in Upstate NY in the Mts. Have to admit, didn't have the guts to let it out above 35mph. Just can't get the fear of potholes in the shade. Call me chicken. Balk, balk.