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Mainshaft clutch gear

There are three variations since 1952.

The mainshaft clutch gear had 18 teeth in 1952 and 1953. In 1954 it changed to 17 teeth.

In 1956 the factory made a running change where some bikes get the older gear and some get the 35449-56 gear. Those gears will interchange in service. The -56 gear lasted until 1966 on all models and until 1969 on kick-start XLCH models.

The -67 gear was used on electric-start models with the dry clutch from 1967 to 1970, and also the 1970 XLCH model used it as well. In 1970 the facotry used the same cases and internals for all the models.

The 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 clutch 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.

35450-52

18 teeth, 1952, 1953

35450-54

17 teeth, 1954 to 1956 to engine # 56KH-1465

35449-56

17 teeth, from engine # 56KH-1465 in 1956 to 1966 all, 1967 to 1969 XLCH

Sportster 35449-56 Clutch-gear

Sportster 35449-56 Clutch-gear, 1956-E1957 ?
This clutch gear does not have an O-ring groove on the 37538-56 clutch gear extension. Either this part was fabricated as a one-off by a mechanic, or it is for 1956 to E 1957, when the O-ring is not called out in the parts books. Problem is, there is only one part number for the extension, so this would have to be like the GM ignition switch where an engineer changed the part and did not up-rev the service part number.

35449-67

17 teeth, 1967 to 1970 XLH, 1970 XLCH

This gear is used on electric start models with a dry clutch. It is longer than either the earlier or later gears. This provides for the electric start dry clutch basket that has two Torington bearings to give it stability.

35449-71

17 teeth, 1971 to 1978

This gear is the wet clutch gear used from 1971 to 1978. It may interchange with the -79 gear below, investigation is on-going.

35449-79

17 teeth, 1979 to 1984

The only difference I see is that the thrust washer next to the Torrington needle bearing is thinner, meaning the gear has a shallower pocket for the bearing and washer. This has the effect of moving the Torrington 0.020" outboard. Many transmission gears changed in 1979, but they usually will retrofit. The only real change I have found is the snap rings that hold in the bearing for this gear are wider.

The wet clutch gear (above) is shorter than the the electric start dry clutch gear (below). There are three types of clutch gears. The bushing in the end of the wet clutch gear on the far left is not standard. It may have been fabricated by a mechanic for some unknown reason. You ca see the right mainshaft is longer for the electric start -67 clutch gear.