They are classed by engine size. Class M (midget) is 7.5 cubic inches. Mainly for lighter weight people. they put out 7 to 10 HP, The record in the 1940s was 42 MPH. Class A is 15 cubic inches. Speeds in the 50s. B class in 350CC – speeds in the high 50s – C class – 500 cc – 31 cubic inches, Speeds in the 60s.
Antique C class is popular. most running PR Johnsons or Modified Evinrude Speeditwins. The Japanese Yamato is a more modern racer and gives a good boat ride. For REALLY antiques – The Elto high speed Speedster was a nice hotrod of the late 1920s. The Elto Quad was also a head turner in it’s day. The first four cylinder outboard that started the horse power race that was brought to a halt by the "Great Recession" of the early ’30s . . . 😀
