Honda CB50 / CB50J / XL50 Workshop Manual, 1977

This factory shop manual covers the 1977 Honda CB50J and XL50, with service information for General, Belgian, German, and Austrian types. Exploded views carry much of the repair coverage, tying component order to inspection, adjustment, and reassembly notes.

PDF Search, Diagram Detail, and Page Count

Text search and wiring detail: Text search is limited to section headings; the workshop text, specifications, and diagram labels are not searchable. There are no embedded PDF bookmarks. Small wiring labels require enlargement, and some remain faint.

The ZIP download contains one printable English-language PDF with 102 pages, including one added cover page and one duplicated XL50 German-type wiring-diagram page. Some wiring diagrams have multilingual legends; the service instructions are in English.

Engine Overhaul, Chassis Service, and Electrical Testing

The following selected coverage highlights the main workshop sections. Additional topics include air-cleaner maintenance and fuel-cock service.

• Engine repair: Engine removal and installation, cylinder-head and valve service, valve-seat refacing, valve-guide replacement and reaming, piston inspection, and cam-chain adjustment.

• Clutch and transmission: Wet multi-plate clutch, oil pump, gearshift mechanism, kick starter, crankshaft, and four- and five-speed transmission disassembly, inspection, and reassembly.

• Carburetor service: Teardown, float and jet inspection, idle and throttle adjustment, and separate factory settings for the covered models and market types.

• Brakes and chassis: CB50J mechanical front-disc/caliper service, XL50 front-drum work, wheel bearings, steering-head races, front-fork overhaul, rear suspension, and drive-chain procedures.

• Electrical diagnosis: Symptom-based troubleshooting charts, ignition and charging tests, switch-continuity checks, cable and wire-harness routing views, and model- and market-specific wiring diagrams.

It is suited to mechanics and experienced owners who already understand basic four-stroke service, since Honda presents the work concisely and uses measuring equipment and model-specific service tools.

Model and Market Differences

Separate data covers General versus Belgian, German, and Austrian camshaft dimensions and wear limits; carburetor setting marks and jet/needle calibration; ignition-advance checks; charging output; battery and fuse arrangements; final-drive selections; and switch circuits.

These distinctions help match inspection data and electrical tests to the model and market type being serviced.

Engine and Drivetrain Repair Depth

The engine chapters include step-by-step procedures for valve-seat refacing and lapping, valve-guide replacement and reaming, valve timing, and front-fork disassembly and assembly. Internal engine coverage extends to A.C. generator removal, crankcase separation, transmission and shift-fork assembly, crankshaft checks, and kick-starter indexing.

Standard-versus-service-limit tables address the cylinder, piston, rings, valves, camshaft, clutch, oil pump, shift forks, connecting rod, crankshaft, bearings, brakes, wheels, and suspension. Component-specific torque tables, lubrication points, fluid capacities, and the maintenance schedule support inspection and final setup.

Tool planning: Listed Honda tools include the tappet adjusting wrench 07908-0010000, clutch holder 07923-1070001, flywheel holder 07925-0010001, flywheel puller 07933-0010000, front-fork disassembling tool 07959-2680000, and rear-shock compressor 07959-3290000. These references help identify the fixtures used in the illustrated jobs before disassembly begins.

Reversing the valve-guide reamer during withdrawal can scratch the finished guide and allow oil into the combustion chamber. The timing-gear section also warns against scribing the crankshaft’s oil-seal contact surface, where an alignment mark can damage the sealing land.

Frame and Electrical Fault Finding

Chassis inspection covers axle bend, wheel runout, bearing play, brake wear, fork components, and rear-shock condition. Brake chapters warn against oil or grease contaminating friction surfaces.

The Oil Flow drawing traces engine lubrication. Separate Cable Routing and Wire Harness Routing views show each model’s control-cable paths and electrical installation.

The Ignition and Charging Circuit drawings distinguish regional electrical arrangements. Charging-current tables, stator and rectifier continuity tests, ignition-coil tests, condenser-capacity checks, and switch-contact charts support fault isolation. Symptom charts connect starting trouble, power loss, smoke, clutch faults, shifting problems, and chassis complaints to checks and possible causes.

Selected Carburetor and Brake Inspection Data

The carburetor table specifies a float height of 20 mm for the General-type CB50J and 21.5 mm for Belgian, Austrian, and German CB50J versions. The illustrated measurement uses a closed float valve with the float tip just contacting it.

For the CB50J front brake disc, standard thickness is 4.9–5.1 mm, with replacement at 4.0 mm. The XL50 front brake lining is listed at 4.0 mm standard thickness, with a 2.0 mm replacement limit measured at the most worn section.