Suzuki LT250R 1986 ATV Service Manual (P/N 99500-22041-01E)

This Suzuki LT250R factory service manual, P/N 99500-22041-01E, copyright 1985, combines the LT250RF base procedures with Section 9 for the 1986 LT250RG Quad Racer. The foreword notes that country-market machines may have minor statutory differences from the standard specification.

Searchable PDF and Chapter Bookmarks

Search and diagram detail: The PDF has searchable OCR text, though recognition errors can affect exact matches. Embedded bookmarks cover the main chapters, wiring diagram, and LT250RG supplement. Small wire-color labels are best read with zoom.

One printable 204-page PDF contains five opening pages, 182 base-manual pages, and the 17-page LT250RG supplement. Five blank pages are already included in that total.

Engine Overhaul, Chassis Repair, and Electrical Diagnosis

The following selected service topics show the repair and diagnostic coverage rather than reproduce the full contents. Other included subjects include fuel/oil recommendations and break-in guidance.

• Engine overhaul: Step-by-step engine removal, crankcase separation, and reassembly, with crankshaft shim selection and cylinder, piston, ring, and reed-valve inspection.

• Clutch and shifting: Clutch disassembly, plate and spring inspection, kick-starter service, transmission overhaul, and gearshift mechanism inspection and assembly.

• Fuel system: Fuel-cock service, carburetor removal and cleaning, needle-valve inspection, float-height adjustment, and condition-specific jetting tables.

• Cooling system: Radiator removal, cooling-system leak checks, radiator-cap testing, and water-pump disassembly, seal inspection, and reassembly.

• Chassis and brakes: Wheel, tire, and hub-bearing service; hydraulic brake repair and bleeding; steering and toe-in adjustment; rear-axle and Full-Floating suspension work.

• Electrical diagnosis: Magneto and ignition-coil tests, CDI fault isolation, AC lighting checks, switch-continuity charts, and the full wiring diagram.

• Maintenance and tune-up: Factory intervals, lubrication points, and drivetrain, fuel, cooling, brake, steering, and chassis checks, with more frequent servicing under severe conditions.

Suzuki wrote this manual primarily for experienced mechanics, while also addressing apprentices and do-it-yourself mechanics; internal engine and hydraulic-brake work assumes proper shop tools and established service practices.

How the 1986 LT250RG Coverage Works

The 1986 material is a differential supplement. Section 9 directs the reader to the LT250RF chapters wherever no G-model difference is listed and marks changed service data with asterisks. The listed component changes apply from the first production of the LT250RG.

Engine and transmission changes: Suzuki documents revised cylinder port shape and timing, a different cylinder-head gasket, and altered fourth- and top-gear components. Updated clutch wear specifications and radiator-cap test data also appear in the supplement.

Fuel and ignition: The G-model's MIKUNI VM34SS receives its own condition-based jetting table, while the RF procedures use the VM32SS. Magneto/CDI revisions also change the ignition specifications. These distinctions matter when selecting carburetor parts, electrical test data, or baseline settings.

Chassis changes: The supplement distinguishes the ring-type RF rear-shock adjuster from the G-model slide type and documents the revised spring-preload setup. It also covers muffler changes, rear brake-pad thickness, the under-guard, rear brake reservoir, and radiator and reservoir hose routing.

Internal Engine and Chassis Inspection

Engine measurements: The overhaul chapter explains crankshaft runout checks, cylinder and head distortion inspection, bore and piston measurement locations, piston-ring limits, and reed-valve clearance. Clutch and transmission inspection extends to plate wear, spring free length, and shift-fork-to-groove clearance.

Chassis assemblies: The brake chapters cover twin front discs, the rear hydraulic disc, and caliper and master-cylinder internals. Steering knuckles, tie rods, and double-wishbone arms have their own removal and inspection procedures.

Rear-axle housing, swingarm, cushion-lever, and cushion-rod sections address bearing removal and reassembly. Final checks link the completed suspension work to chain, brake, tire, and fastener adjustments.

Fault Charts, Diagrams, and Shop References

Troubleshooting tables connect symptoms, possible causes, and remedies for hard starting, stalling, engine noise, clutch slip or drag, shifting faults, carburetor overflow, and overheating. Separate tables address ignition and lighting faults, handling complaints, suspension trouble, and hydraulic-brake problems.

Illustrated references include the counter-balancer operation diagram and carburetor slow-, main-, starter-, and float-system diagrams. A water-pump exploded assembly, CDI ignition schematic, AC lighting schematic, full wiring diagram, and wire, cable, and hose routing views support component inspection and installation.

The service-data section supplies component-specific torque tables, a general fastener chart, fluid recommendations and capacities, wear limits, clearances, electrical test values, and adjustment data.

The 39-item special-tool list identifies 09920-13120 for crankcase separation, 09910-32812 for crankshaft installation, 09920-53710 for holding the clutch sleeve hub, and 09930-40113 for holding the rotor.

Crankshaft and Brake Service Cautions

The engine reassembly notes warn that tapping the crankshaft into the crankcase can disturb crankshaft alignment. The brake chapters identify high-pressure air as a caliper-piston damage risk and prohibit solvent or gasoline when cleaning hydraulic components.

Read the factory precautions before beginning repair work. They cover ventilation when running the engine, flammable fuel, brake-fluid leakage, tire inflation, replacement circlips, and post-service operational checks.

Preview of LT250RG Clutch and Radiator Test Data

The LT250RG clutch table gives a standard drive-plate thickness of 2.7–2.9 mm and a service limit of 2.4 mm. The engine chapter describes the corresponding plate inspection.

The G-model radiator-cap valve-release specification is 110 ± 15 kPa. This is the cap-test value; the cooling chapter also describes a separate cooling-system leak test.