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Mainshaft 3rd gear

This gear has been the same since 1956.
The mainshaft 3rd gear has not changed much since 1956. The factory did change the number of teeth on the earliest gear, from 21 to 20 in K-models and Iron Sportsters from 1954 to 1984.

Sportster_MainshaftThe Iron Sportster mainshaft is a triumph of engineering. The general design has sustained from 1952 to 1984. There were teething problems in the early K-model, but they were all cured by 1957 with the introduction of the Sportster.

Mainshaft second gear is in the darker oval. Gears are named for carrying power, not the order on the shaft. The gears from left to right are mainshaft low, mainshaft 3rd, mainshaft 2nd, and the clutch gear.
Bottom of first column move down to the left


21 teeth, 1952, 1953


20 teeth, 1954, 1955


20 teeth, 1956 to 1978
Sportster_35305-56_Mainshaft-3rd-gear_1956-1978_tp.jpgSportster 35305-56 Mainshaft-3rd-gear, 1956-1978


20 teeth, 1979 to 1984
The part changed to a 35305-56A in 1979, which should retrofit with this gear. Letter suffixes usually mean the part is very similar and will replace the part with no letter suffix.
move up a little to the right This is the end.