Big differences ...
The Classic 1-CR is the first wide nozzle machine Kirby made. It has no scuff plate where the power switch and cord connect to the machine. The head light is still the 110 volt bulb like the previous model Kirbys. Motor wise, it is almost identical to the D-50 and D-80, and uses the same speed selector/safety switch. As a matter of fact, you could swap out the Classic rug nozzle with a D-50 or D-80 nozzle, and it would work just fine. Starting with the Classic Omega 1-CB on, the motor, wiring, head light, and bearings were all redesigned. The head light went to a 12 volt automotive type bulb that got powered by tapping the field coil and was enclosed in a lens assembly. This protected the bulb, and added greater life. Motor bearings are sealed. Speed selector/safety switch was redesigned and lasted through the Tradition without modification (except for that debacle when Kirby tried to move it to the headlight cap on the first run Traditions. Boy what a mess). Heritage through the Legend II marked the next big change in Kirby's design followed by the G series.