2004 Yamaha TT-R125 / TT-R125E / TT-R125LW / TT-R125LWE Owner's Service Manual (P/N 5HP-28199-85)

Yamaha’s factory Owner’s Service Manual for the 2004 TT-R125 family covers the TT-R125(S), TT-R125E(S), TT-R125LW(S), and TT-R125LWE(S). This is more than an operator’s handbook: its sequential format combines operation and scheduled maintenance with exploded-view removal, disassembly, inspection, repair, reassembly, and adjustment procedures. It is suited to experienced owners and mechanics who can use the specified Yamaha service tools and electrical measuring equipment; routine maintenance is approachable, but internal engine, hydraulic-brake, suspension, and electrical repair assumes workshop-level skills.

• Publication details: A 610-page PDF in English, French, and German; Yamaha P/N 5HP-28199-85, 1st Edition, March 2003.
• Variant-specific coverage: Separates the kick-start TT-R125/TT-R125LW systems from the electric-start-equipped TT-R125E/TT-R125LWE, including their starter clutch, starter motor, battery, interlock, CDI magneto, and charging-system differences.
• Engine repair: Covers carburetor removal and disassembly, cylinder-head and cam-timing work, camshaft and rocker arms, valves and springs, cylinder and piston, engine removal, crankcase separation, crankshaft and balancer, and five-speed transmission service.
• Clutch and supporting systems: Details clutch and primary driven gear repair, oil-pump inspection, kick-axle and shift-shaft service, CDI rotor/stator work, and E/LWE starter-clutch inspection and assembly.
• Chassis procedures: Distinguishes standard-model front drum-brake service from LW/LWE hydraulic front-disc work, then covers wheels, rear drum brake, brake bleeding, front fork, steering, swingarm linkage, and rear shock removal and adjustment.
• Inspection and setup: Provides maintenance schedules plus procedures for valve clearance, carburetor fuel level and idle settings, oil-pressure checks, drive-chain adjustment, steering-head setup, brake wear, wheel runout, battery charging, fuse checks, and LWE suspension adjustments.
• Diagrams and diagnostics: Includes model-specific cable-routing and wiring diagrams, ignition fault-isolation charts, electric-start and charging-system inspection charts, exploded assemblies, torque tables, fluid data, wear limits, and electrical test specifications.

Model and Configuration Details

The specification tables identify regional model names and codes, which helps match the manual before ordering parts. TT-R125 uses 5HPP/5HPR, TT-R125E uses 5HPS/5HPT, TT-R125LW uses 5HPU/5HPV, and TT-R125LWE uses 5HPW/5HPX. The “S” model-name suffix appears in the USA, Canada, Australia, and New Zealand listings; Europe and South Africa use the names without that suffix.

Standard-wheel TT-R125 and TT-R125E models use 17-inch front and 14-inch rear wheels with drum brakes at both ends. LW and LWE versions use 19-inch front and 16-inch rear wheels, a hydraulic front disc, and a rear drum. The E and LWE retain kick starting while adding electric start. The LWE also receives separate front-fork preload and rear-shock compression/rebound adjustments, along with a reservoir-equipped shock layout.

Workshop Procedures and Factory Data

Removal sections begin with exploded views and job charts showing parts, work order, and the minimum extent of disassembly. The manual supplies YM/YU/YS tool references for the USA and Canada and 90890-series equivalents for other markets. Examples include the YU-1135-A/90890-01135 crankcase separator, YU-33270-B/90890-01362 flywheel puller, YM-4019/90890-04019 valve spring compressor, YM-33963 and YM-33281 fork-seal drivers, and YU-3112-C/90890-03112 pocket tester.

The tables provide component-specific tightening sequences and torques, capacities and approved lubricants, service limits, clearances, spring and brake specifications, and test values for the ignition and source coils, charging circuit, relays, switches, and starter motor.

Diagrams, Diagnostics, and Repair Boundaries

Visual references include separate TT-R125/TT-R125LW and TT-R125E/TT-R125LWE wiring diagrams, matching cable-routing layouts, an ignition-system inspection flowchart, an electric-start inspection flowchart, and a charging-system inspection flowchart. Electrical diagnosis is concentrated in those ignition, starting, and charging circuits rather than a general symptom-based troubleshooting chapter.

The crankcase section warns that forcing unevenly separated case halves can damage their mating surfaces, while the cam-timing section notes that turning the crankshaft during sprocket installation can cause engine damage or incorrect valve timing. For LW/LWE brake repair, the manual requires new caliper seals after disassembly and warns that spilled brake fluid can damage paint and plastic.

The nitrogen-charged rear shock is covered for removal, inspection, adjustment, and replacement, not internal overhaul. Yamaha warns against opening it, and pressure release for disposal is identified as dealer-only work. Follow the manual’s precautions for fuel, hot or moving engine parts, hydraulic brakes, electrical testing, and the pressurized shock.