Honda CB125/175 & CL125/175 Shop Manual Set, 1967–1973 (P/N 6230401)

Use the publication that matches the engine family and model configuration. The TL125 supplement refers back to procedures in the single-cylinder base manual, while the separate CB125/CB160 publication covers a different twin-cylinder application.

PDF Search, Diagram Detail and File Contents

Search and diagram detail: None of the three PDFs supports text search or includes embedded PDF bookmarks. Small wire-color codes in the dense CB/CL and 100/125 wiring diagrams require zooming; the CB125/CB160 circuit illustrations have more readily readable labels.

The ZIP download contains three printable English PDFs totaling 449 pages. This includes the three original covers, two memo pages and three blank pages, together with the forewords, contents, index and included supplements.

Engine Rebuilds, Carburetor Adjustment and Electrical Testing

The following selected repair topics show the scope of the publications rather than reproduce their complete contents. Further topics include fuel-strainer servicing and exhaust-pipe and muffler removal.

• Engine repair: Step-by-step engine removal and installation, cylinder-head disassembly, valve-guide and seat service, piston inspection, and crankcase separation.

• Lubrication and clutch: Oil-pump and centrifugal-filter service, wet-clutch disassembly, friction-disc inspection, and clutch-release adjustment.

• Transmission service: Internal gearbox disassembly, shaft and gear inspection, shift-drum and fork service, and kick-starter assembly details.

• Fuel-system adjustment: Variable-venturi carburetor construction, float-level measurement, mixture adjustment, and twin-carburetor synchronization.

• Chassis and brakes: Telescopic-fork service, steering-bearing inspection, swing-arm checks, wheel-bearing work, and drum-brake wear assessment.

• Electrical diagnosis: Ignition-coil and condenser tests, generator and rectifier checks, charging-current measurements, starter-motor inspection, and model-specific wiring diagrams.

These manuals are suited to service technicians and experienced owners comfortable with internal engine work, precision measurements and the dedicated tools specified for the procedures.

Cylinder Heads and Internal Engine Inspection

The CB/CL manual separates the twin-cylinder engine sections and collects revised K3 procedures in its supplement. Component-specific torque tables, piston and connecting-rod inspection data, crankshaft wear limits, valve-tappet information and lubrication capacities support decisions about parts reuse and reassembly.

Engine assembly drawings and the CB125 and CB160 exploded view help identify parts by location and orientation during a teardown.

The CB/CL175 cylinder-head section warns that uneven tightening can crack or warp the head and compromise its seal. The CB125/CB160 assembly notes also identify reversed piston installation as a cause of piston-to-valve contact.

Gearbox Relationships and Carburetor Settings

Gearbox coverage goes beyond external adjustment. The sectional view of the gear-shift drum and the transmission operating illustrations show how the selector, forks and gears interact, helping preserve component order and engagement relationships during internal repair.

The carburetor sections explain the main and slow circuits, jet-needle operation and float-valve behavior. Sectional carburetor views accompany model-specific setting tables and adjustment procedures, including the relationship between the two carburetors on the twins.

The TL125 supplement identifies its changed clutch arrangement and transmission components and directs the reader to the applicable base-manual procedures.

Ignition, Charging and Starting Circuits

Separate CB175 wiring diagrams cover General Export and U.S.A. Export configurations. Matching the motorcycle to the appropriate regional diagram matters before testing or replacing electrical parts.

Charging-system material includes generator output, rectifier checks and charging-current measurements. Starter coverage includes motor disassembly, brush inspection and solenoid operation; troubleshooting tables link symptoms with probable causes and corrective actions.

The TL125 wiring diagram covers its flywheel-magneto ignition circuit. The CB125/CB160 publication adds ignition-coil, rectifier and starter-clutch construction illustrations.

Chassis Service and Workshop Equipment

Chassis inspection data covers fork components, steering bearings, swing-arm pivots, wheel alignment and brake wear. In the single-cylinder 100/125 manual, a defective rear shock-absorber damper body is treated as a replacement unit rather than an internally repairable assembly.

Factory-tool reference lists identify the equipment expected for engine and chassis work. Examples in the CB/CL manual include generator-rotor puller 07933-2160000 and valve lifter 07957-3290000, allowing the required tooling to be checked before disassembly.

Vintage fuel and electrical work carries fire and shock risks. Work should be performed with the fuel supply controlled, the battery and circuits isolated as required, and normal professional shop-safety procedures in place before inspection or testing.

Examples of Ring-Gap and Starter-Brush Limits

For CB/CL175 piston-ring inspection, the listed ring end-gap range is 0.15–0.40 mm, with replacement specified above 0.8 mm.

The CB125/CB175 starter-motor section lists a standard brush length of 11–12.5 mm and a replacement limit below 5 mm. These inspection references distinguish standard dimensions from wear limits.