Suzuki GS850G 1978–1983 Service Manual Set (P/N 99500-38002-03E)

The larger volume combines base chapters with later-model supplements, which must be used with the sections they reference. The separate GN publication provides earlier base material, including differences between market specifications.

PDF Search, Bookmarks, and Wiring Detail

Search and diagram detail: The June 1983 PDF supports OCR text search through most chapters and has 26 bookmarks; some links land just before the named section. The February 1979 PDF has no text search and uses individual-page bookmarks labeled with image filenames. Small wiring labels require zooming in the later volume; some labels in the earlier wiring diagram remain blurred when enlarged.

The ZIP contains two printable English PDFs totaling 660 pages. This includes six pages in the larger volume comprising its cover, two group-index pages, foreword, introductory side-view page, and publication-details page.

Engine Overhaul, Shaft-Drive Setup, and Electrical Diagnosis

The following is a selection of covered work, rather than a complete contents list. Other topics include initial battery preparation and pre-delivery inspection.

• Engine repair: Engine removal and installation, compression testing, cylinder-head and valve service, camshaft and cam-chain work, and piston and cylinder inspection.

• Clutch and transmission: Clutch disassembly and inspection, transmission-shaft service, gear-shift mechanism checks, crankcase work, and crankshaft inspection.

• Shaft-drive setup: Secondary and final bevel-gear disassembly, bearing-preload adjustment, shim selection, backlash measurement, tooth-contact inspection, and propeller-shaft installation.

• Fuel-system service: VM26SS and BS32SS carburetor disassembly, float and fuel-level checks, carburetor synchronization, fuel-cock operation, and emissions-related servicing requirements.

• Electrical diagnosis: Ignition and charging tests, starter-motor inspection, lighting diagnosis, self-canceling turn-signal troubleshooting, and model-specific wiring diagrams.

• Brakes and chassis: Front-fork overhaul, wheel and steering service, master-cylinder and caliper repair, brake bleeding, and cable and hose routing.

Its depth and reliance on precision measurement, carburetor balancing equipment, and Suzuki service tools make it best suited to experienced mechanics and advanced DIY owners.

Model Changes and Supplement Use

GN to GT: The base model uses breaker-point battery ignition and combined electric/kick starting. The GT material documents transistorized ignition, electric-only starting, revised brakes, and the change between the two carburetor types. These distinctions matter when selecting fuel-system and electrical procedures.

GX/GLX revisions: The supplement identifies camshaft-sprocket fastener changes, driven-gear shift-fork and shift-spring revisions, and changes to the universal-joint flange and propeller shaft. Its camshaft-fastener comparison also distinguishes interchangeable arrangements from the later arrangement that requires matching components.

GZ and GLD ignition: These sections cover electronic timing advance and ignitor/signal-generator testing. The GZ cylinder-head and head-cover revision begins at engine No. GS850G-155015, with illustrations of the early and late arrangements and the associated cam-timing reference.

Internal Engine Inspection and Adjustment

Step-by-step procedures cover valve-guide replacement and reaming, valve-seat servicing, cam timing, and cam-chain tensioner inspection. Piston-ring checks, camshaft-journal measurements, and cylinder-head inspection connect the repair procedures with their service limits.

Lower-end coverage extends to transmission shafts, shift components, clutch assembly, oil-pump inspection and pressure testing, and final operational adjustments. Separate troubleshooting tables address engine, chassis, and electrical faults. The compression-test section lists gauge 09915-64510.

Bevel-Gear Measurement and Final Assembly

The shaft-drive chapter pairs bearing and seal procedures with shim tables, backlash measurements, and tooth-contact pattern illustrations. Its final gear case breather-circuit view shows how air and oil move through the housing.

The manual lists secondary-drive bevel-gear holder 09924-54511 and backlash measuring tool 09924-34510. Its assembly cautions emphasize retaining the shims and treating the drive and driven bevel gears as a matched pair; incorrect parts or shim placement can upset bearing preload and tooth contact.

Carburetors and Electrical Fault Tracing

Carburetor service includes balancer calibration and synchronization, with balancer 09913-13121 and BS32SS fuel-level gauge 09913-14511 identified. The emissions sections distinguish factory-set mixture components from the adjustments covered by the service procedures.

Electrical coverage includes generator and regulator/rectifier checks, starter-circuit and motor inspection, gear-position indicator checks, and fuel-gauge diagnosis. Transistorized-ignition and electronic timing-advance diagrams accompany the applicable model procedures.

Forks, Brakes, and Workshop Reference Data

The GLX supplement contains a separate front-fork overhaul with assembly views and component inspection. Wire, cable, and rear brake-hose routing illustrations complement the chassis procedures.

The GT routing cautions address clutch-cable contact with the cylinder head, while brake notes flag fluid-related damage to hydraulic components and finishes. Engine and chassis torque tables are supplemented by bolt-grade charts, wear limits, clearances, fluid specifications, capacities, and electrical test data.

Brake, steering, wheel, and driveline repair can directly affect vehicle control. Follow the model-specific cautions, inspection limits, torque data, and final checks before returning the motorcycle to service.

Examples of Valve-Clearance and Ignition Test Data

For the GS850GN, the maintenance chapter specifies intake and exhaust tappet clearance of 0.03–0.08 mm with the engine cold. The accompanying material explains shim selection and the conditions for checking clearance.

For the GS850GLD, ignition inspection specifies approximately 140–180 Ω signal-generator resistance for the Blue–Yellow and Green–Black lead pairs. The adjacent ignitor-unit test diagram keeps these values tied to that ignition configuration.