• 1957-1985 Swingarm Pics and Information
• 1957-1978 Swingarm Assembly

A number of 1972 Sportsters were produced from November 1, 1971 to March 29, 1972 without the (3 position) stake operation performed on the rear left side fork bearing lock nut (47514-52). Bearing pre-load (which should be kept at 1-2 pounds) is controlled by the left and right (47515-52) bearing lock nuts. The affected VINs were (3A or 4A) 18748H2 to 33040H2. This safety defect prompted a recall of the affected bikes with the dealer being required to remove the rear fork for inspection and stake any of them that were done previously at a rate of $7 reimbursed labor and handling. ¹⁾

• Follow the procedure in your FSM to remove the swingarm. However, if you can do it without removing the staked nut on the left side is best. It serves to center the swingarm in the frame and you can bung up the threads on that nut really easily. ²⁾

• Pre-1979, only the 1977 XLCR had the box arm with Disc. ³⁾
• 1979 - 1981 had the box arm with disc and it will fit pre-79 frames. ⁴⁾
• A 79-81 swing arm will bolt on a 72 frame. Things to consider when changing swingarms are master cylinder placement, operation and the fact that the 79-81 swing arm shock mounting will change the angle of your shocks. ⁵⁾
• Consider if you even want a disc on the rear. It won't work any better than the drum, which is already powerful enough to lock up the wheel. Put your effort into improving the front brake if you want to stop better. ⁶⁾ You would do better by adapting a later 39 MM Evo fork for brakes and handling. ⁷⁾

Bearing Kit (47550-74) (replaced the single bearing part # 47521-52) contains 2 bearings which are 0.100“ narrower than the original bearing dims used in Sportsters up to February of 1974. The kit also contains a new pivot bolt nut (47512-74), bearing locknuts (L - 47514-74, R - 47515-74) and an outer spacer (47521-74) - clearanced for the new bearings. ⁸⁾

Caution: Parts must not be intermixed on a complete rear fork pivot shaft and bearing assembly. Correct bearing clearance and specified fork bearing preload cannot be obtained with intermixed parts. Correct bearing preload is essential for satisfactory operation and proper motorcycle handling. ⁹⁾