Harley-Davidson Duo-Glide 74 OHV & Servi-Car 1958–1959 Service Manual (P/N 99482-59)

• Target Models: Built for owners and workshops servicing the 1958–1959 Harley-Davidson Duo-Glide 74 OHV and FL/FLH variants.
• Official OEM Reference: Publication P/N 99482-59, serving as the definitive factory resource for late 1950s Big Twin builds and teardowns.
• 140 Pages of Technical Data: Includes 85+ exploded-view diagrams, transmission gear ratios, and exact valve timing specifications.

Document Coverage and Technical Insight

The 1959 Harley-Davidson Duo-Glide 74 OHV service manual provides the exact mechanical specifications and assembly guidelines needed for the classic Big Twin platform. Whether you are a professional technician or a dedicated DIYer, having the right factory data on hand prevents costly guesswork on the bench. Detailed sections map out the 1,207 cc V-type engine, covering critical ranges like valve spring tension, tappet clearances, and oil pump pressure benchmarks. You will also find comprehensive breakdowns of the Hydra-Glide front forks, outlining proper oil filling methods and bushing reaming procedures.

For drivetrain work, the document dives deep into the transmission and clutch systems. It details 4-speed gear box ratios, shift linkage adjustments, and internal disc clearances. Working on vintage motorcycles requires precision and a strict awareness of mechanical safety; always secure the bike on a stable lift and double-check tension loads before starting heavy teardowns or alignments.

Immediately pull up essential specification data directly on your shop tablet right when you need it. The text highlights crucial assembly tolerances, such as connecting rod alignments, cylinder bore measurements, and piston ring gaps. Factory reference values establish main bearing end play at 0.0001–0.0010 in. for optimized engine rotation, while transmission gear backlash is set at 0.003–0.006 in. And when you are setting up the front end, the guidelines specify exactly 7 oz. of hydraulic fork oil per slider tube for standard units.