Yamaha SRX250T/TC 1987 Service Manual (P/N LIT-11616-06-04)

Yamaha’s service manual for the 1987 SRX250T (2NV) and SRX250TC (2NW), P/N LIT-11616-06-04, first edition, February 1987. It covers periodic maintenance, engine repair, carburetion, chassis service, and electrical diagnosis.

PDF Bookmarks, Search, and Diagram Detail

Navigation and wiring detail: PDF text search is not available. Embedded bookmarks cover the chapters and major sections; the separate “Back to Index” link points to an external file that is not included. Small wire-color and connector labels in the full wiring diagram require zooming. Dark shading reduces contrast in parts of the starting-circuit diagram.

The ZIP download contains one printable English PDF. Its 250 pages include five front-matter pages, six section separator pages, and the original back cover.

Engine Overhaul, Carburetion, and Electrical Fault Tracing

These selected coverage highlights summarize the main workshop areas rather than the complete contents. Further topics include fuel-cock cleaning and headlight-beam adjustment.

• Periodic service: Inspection schedules, adjusting-pad selection, engine oil/filter/strainer service, oil-flow and compression checks, clutch and throttle adjustment, and ignition-timing checks.

• Engine repair: Step-by-step removal, teardown, inspection, and reassembly procedures for the DOHC top end, crankshaft, balancer shaft, oil pump, clutch, starter drive, and transmission.

• Carburetor service: Teikei Y22PV removal, separation, cleaning, diaphragm and coasting-enricher inspection, float and fuel-level adjustment, primary full-open adjustment, and secondary synchronization.

• Chassis service: Wheel service, front-brake caliper and master-cylinder repair, bleeding, fork overhaul, steering-head service, rear-shock removal, swingarm inspection, and chain/sprocket replacement.

• Electrical diagnosis: Starting, charging, ignition, lighting, and signal-system fault tracing, with starter-motor inspection, switch tests, system circuit diagrams, and the full wiring diagram.

Yamaha wrote this manual primarily for its dealers and qualified mechanics. It assumes a basic understanding of motorcycle repair concepts and procedures.

Maintenance and Internal Engine Repair

The valve section shows how to identify installed adjusting pads and use the separate intake and exhaust selection charts. Canister and hose inspection, with matching routing illustrations, applies to the SRX250TC only.

Top-end work: Detailed coverage includes camshaft and cap inspection, valve-guide replacement, valve-seat cutting and lapping, cylinder and piston measurement, and cam-chain timing. The manual also identifies the piston, clutch, carburetor, and AC magneto as components that can be serviced without removing the engine.

Bottom-end work: Inspection extends to crankshaft alignment, trochoid oil-pump clearances, primary gears, clutch wear, transmission shafts and gears, shift forks, shift cam, starter drive, crankcase bearings, and oil seals. Assembly notes address balancer-gear indexing and transmission-operation checks before final crankcase tightening.

The crankshaft/balancer-shaft and transmission/shifter exploded assemblies show component relationships, while the lubrication-flow chart traces oil distribution through the engine.

During cam timing, excessive camshaft rotation can damage the piston and valves. The crankcase-separation guidance also warns that forcing a case half that hangs up can damage the gasket mating surface.

Y22PV Carburetor Circuits and Adjustments

The carburetor section view distinguishes the primary, secondary, starter, fuel, and coasting-enricher circuits. It also identifies which piston, plunger, and float-chamber components can be serviced without separating the carburetors.

Inspection guidance covers the vacuum piston, rubber diaphragms, jet needles, float needle valve, and seat. The adjustment sections distinguish float height, running fuel level, primary throttle opening, and secondary-carburetor synchronization.

Brakes, Forks, and Rear Suspension

Chassis coverage extends to wheel-bearing replacement, rear drum-brake inspection, front-disc measurements, fork seals and damper rods, steering-bearing replacement, swingarm free-play checks, and suspension-linkage service.

The gas-oil rear shock is treated as a replace-as-an-assembly unit rather than an internal rebuild. Spring-preload adjustment and removal/installation are covered.

Safety notes address secure motorcycle support during wheel, fork, and steering work, complete bleeding after the front-brake circuit is opened, and handling restrictions for the pressurized rear shock.

Starting Interlocks and Electrical Troubleshooting

Symptom-based charts address no cranking, no charging, no spark or intermittent spark, inoperative lighting, turn signals that do not cancel, brake- and neutral-light faults, and fuel-meter problems.

The starting-circuit operation diagram explains how the neutral, clutch, and sidestand switches interact with the cut-off relay. Together with the fault-tracing charts, it helps distinguish an interlock fault from a starter-motor problem.

The SRX250T/TC wiring diagram supplies wire-color codes and connector relationships. Cable and harness-routing illustrations provide installation references.

Shop Specifications and Special Tools

Factory tables consolidate tightening torques, oil grades and capacities, carburetor settings, valve and camshaft clearances, piston and crankshaft limits, clutch and transmission wear data, suspension specifications, brake and wheel limits, and electrical test values. Appendices add unit definitions, conversion tables, and lubrication diagrams.

Tool references include the YM-4106 tappet adjusting tool, YM-91042 universal clutch holder, YU-01135 crankcase separator, YU-90050/YM-1383 crankshaft installing set, YM-33256 front-fork cylinder holder, and YU-03112 pocket tester. These references let a repair shop confirm tooling needs before beginning an overhaul or diagnostic job.

Selected Cylinder-Head Clearances and Charging Test Values

The cylinder-head inspection specifies warpage below 0.03 mm and an intake valve stem-to-guide clearance of 0.010–0.037 mm. These entries accompany the head and valve inspection procedures.

For charging-system diagnosis, the troubleshooting chart specifies 14–15 V at 5,000 r/min. The chapter pairs this voltage check with stator-coil testing and wiring checks.