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Mainshaft low gear

This gear has been the same since 1952.
The mainshaft low gear has not changed much since 1952. The factory did change to a dash-A suffix, which will retrofit to the earlier part without a suffix.

The early parts book list both gears as 29 teeth. This is likely a typo.

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.

Sportster-low-gear_highlight.jpgMainshaft low 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


27 teeth, 1952, 1953


27 teeth, 1954 to 1978
Sportster 35277-52A Mainshaft low gear, 1954-1984

The part changed to a 35277-52A in 1954, 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.