Kawasaki KDX 125SR 1990 Service Manual (P/N 99924-1130-01)

This Kawasaki Heavy Industries service manual covers the 1990 KDX125SR, P/N 99924-1130-01, First Edition (1), dated April 30, 1990. Its model-application table identifies KDX125-A1 beginning with frame DX125A-000001 and KDX125-B1 beginning with frame DX125B-000001.

PDF Search, Chapter Bookmarks and Diagram Detail

Search and diagram readability: Text search is partially usable because the existing OCR contains recognition errors and omissions. Embedded bookmarks provide chapter navigation. Some small labels and faint lines in the main wiring diagram remain difficult to read even when enlarged.

The ZIP download contains one printable English PDF. Its 211-page total includes the front cover, quick-reference guide, title/copyright page, rear model-application page and four repeated pages.

Two-Stroke Engine, Chassis and Electrical Service

These selected topics outline the repair coverage; additional material includes air-cleaner servicing.

• Fuel and oil injection: Carburetor removal and disassembly, fuel-level checks, reed-valve inspection, throttle and oil-pump synchronization, oil-pump bleeding and delivery testing.

• Engine repair: Engine removal, compression testing, cylinder-head and piston service, KIPS exhaust-valve work, and expansion-chamber and silencer removal.

• Clutch and transmission: Clutch inspection, primary-drive and kickstarter service, crankcase splitting, transmission-shaft disassembly and reassembly, and shift-mechanism inspection.

• Cooling system: Coolant replacement, pressure testing, radiator-cap checks, water-pump and seal service, thermostat testing, and water-temperature sensor inspection.

• Brakes and chassis: Wheel and hub-bearing service, chain and sprocket inspection, caliper and master-cylinder repair, brake bleeding, front-fork disassembly, Uni-Trak linkage and steering service.

• Electrical diagnosis: Wiring diagrams, charging and ignition tests, regulator/rectifier checks, lighting and meter service, switch and sensor inspection, and oil-level warning troubleshooting.

The repair material is suited to technicians and experienced owners who already understand basic motorcycle service and have access to the specified pullers, drivers, gauges, and electrical test equipment.

Fuel Delivery and Internal Engine Repair

The Keihin PE28 carburetor and Kawasaki Superlube oil-injection sections explain their linked cable adjustments. Oil-pump coverage extends to check-valve inspection, but an internal pump fault requires assembly replacement rather than individual-part repair.

Top-end inspection covers piston rings, ring grooves, piston pins and connecting-rod small ends. KIPS material includes valve removal, installation, positioning and operating checks. The ELECTROFUSION cylinder cannot be bored or honed; the manual specifies replacement when wear exceeds its limits.

Right-side engine work includes clutch plates, springs, hub and housing inspection, the exhaust advancer, external shift mechanism and oil-pump idle gear. Step-by-step procedures cover crankcase splitting and transmission-shaft disassembly and reassembly, with inspections of shift drums, forks, gear dogs and bearings.

Bottom-end coverage limit: Crankshaft and connecting-rod material includes big-end inspection and runout measurement. Printed pages 8-7 and 8-10 are absent, leaving crankcase assembly and crankshaft alignment coverage incomplete.

Cooling-System Checks and Water-Pump Seals

Water-pump instructions address the shaft, impeller, mechanical seal and oil seal. Radiator, filler-neck and hose inspections accompany the cooling-system pressure tests.

The water-pump section warns that an obstructed seal drainage passage can force coolant past the oil seal into the transmission oil.

Brake, Suspension and Steering Work

Wheel service extends to spokes, rim and axle runout, tires and the speedometer drive. Brake sections describe caliper and master-cylinder disassembly, inspection and reassembly.

Master-cylinder coverage limit: Printed page 11-10 is absent, interrupting the removal instructions. The brake chapter also warns that mixing fluid types or brands can reduce the boiling point and damage rubber components.

Front-fork work covers guide bushes, seals and springs. Rear chassis procedures address the Uni-Trak tie-rods, rocker arm, swingarm and steering-stem bearings. Rear-shock coverage is limited to spring-preload adjustment and removal and installation, without an internal shock rebuild.

Charging, Ignition and Warning-Circuit Diagnosis

Electrical tests cover flywheel magneto output, charging coils, regulator/rectifier circuits, ignition-coil windings, pickup and exciter coils, and the CDI system’s IC igniter. Battery, lighting, meter, switch and sensor procedures are also included.

The engine-oil-level warning checks distinguish bulb, power-supply, wiring and sensor faults, helping narrow the cause before components are replaced.

Visual references include the Wiring Diagram, Cable, Wire, and Hose Routing layouts, Cooling System flow view, Exhaust Valve Position illustrations, Ignition System Wiring Diagram, and Engine Oil Level Warning System Wiring Diagram.

Workshop Tools and Factory Reference Data

Compression testing names Gauge 57001-221 and Adapter 57001-1159. Bottom-end procedures call out Crankcase Splitting Tool Assembly 57001-1098 and Crankshaft Jig 57001-1174.

Other named tools include Fork Oil Seal Driver 57001-1219, Flywheel Puller 57001-252, and Hand Tester 57001-983.

Reference material includes a periodic maintenance chart, torque tables, fluid and capacity data, wear limits, electrical test values and symptom-based troubleshooting. Market notes distinguish U.K., French, Greek, Italian, Norwegian, Swiss, South African, Swedish and West German specifications.

Exploded views show assembly relationships; this is not a parts-number catalog or a frame-straightening guide. Follow the manual’s warnings for fuel, hot coolant, batteries, supported assemblies and hydraulic brake work, and use a qualified technician when the job exceeds your training or equipment.

A Preview of Thermostat and Temperature-Sensor Test Values

Thermostat inspection specifies a valve-opening range of 58.5–61.5°C, alongside the component’s removal and installation notes.

For the water-temperature sensor, the electrical chapter lists approximately 130 Ω at 80°C and 70 Ω at 100°C. Its test illustration shows the sensor and thermometer arrangement used for this resistance check.