Description
Original Equipment Manufacturer (OEM) Harley-Davidson Ironhead Sportster 4-Speed Complete Transmission Gearset & Trapdoor Assembly.
- Trapdoor Casting Part Number: 34845-54 A / 34845-54A
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Configuration: Complete "Cassette-Style" drop-in transmission package.
Up for sale is a genuine vintage factory Harley-Davidson 4-speed transmission complete gearset cluster assembly. Removed directly from a vintage Ironhead Sportster engine block, this is an authentic US-made structural unit. This comprehensive rebuild package features the mainshaft, countershaft, all 4 factory gear ratios, engagement sliding clutches, shifting forks, and the shift cam drum mechanism already pressed into the structural aluminum bearing trapdoor housing panel.
Avoid the headache of buying loose individual transmission shafts, vintage gears, and shifting forks that require specialized hydraulic press machinery and complex dial indicator shimming. This pre-assembled cassette grouping slides directly into your split crankcase engine bore, saving you hours of specialized labor and setup tool requirements. It is a vital asset for fixing a bike with a blown gearbox, stripped primary output splines, or building out empty vintage cases.
🏍️ Fitment & Vehicle Compatibility:
Direct factory drop-in application for standard right-side 4-speed manual transmission crankcases across the Ironhead generation:
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Harley-Davidson Ironhead Sportster Series: Fits classic 1954 to 1985 XLH, XLCH, Custom, and Roadster 900cc / 1000cc configurations. (Always cross-reference your specific shifting shaft spline depth and year-specific case offset to guarantee a perfect install).
🔍 Condition Notes:
This is a pre-owned vintage factory engine takeoff assembly.
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Gears & Dogs: All individual gear teeth profiles are structurally sound and true, without severe pitting or heavy step-wear ridges along the contact faces. The engagement slider dogs feature square, sharp tracking corners.
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Shafts & Splines: The transmission mainshaft splines and output sprocket threads are deep, clean, and entirely free of wallowing or twist damage.
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Trapdoor & Assembly: The aluminum mounting door plate is straight with fully intact bolt-hole ears. The shifter cam mechanism clicks cleanly into gear paths, and the gears rotate smoothly, though cleaning, re-oiling, and replacing old seals is highly recommended prior to locking down down your engine case rebuild.
Fast shipping with tracking included. Please carefully inspect all gear teeth and shifting profiles in the photos to confirm it fits your specific vintage project layout.
