Honda NRX 1800 Valkyrie Rune 2004–2005 Service Manual (P/N 61MEC00)

Honda’s factory service publication for the 2004 NRX1800 Valkyrie Rune, P/N 61MEC00, was issued in May 2003. Its 24 numbered sections cover model-specific maintenance, diagnosis, and repair.

PDF Search, Navigation, and Page Count

Text search and diagrams: Main text is searchable, with embedded bookmarks for chapters and subsections. Small labels in the full wiring diagram require zooming and are not searchable. The “Home Page” bookmark points to a separate file that is not included; “Symbols” opens the contents page.

Supplied as one printable, English-language PDF inside a ZIP download. The 552-page PDF includes three introductory pages and 13 memo pages within the total.

Engine, PGM-FI, and Rune Chassis Service

The following selected coverage highlights are not a complete contents list. Other topics include body-panel and exhaust-system removal, plus symptom-based troubleshooting for starting, power loss, and handling problems.

• Engine repair: Step-by-step engine removal and installation, compression testing, cam-chain work, cylinder-head disassembly, valve-guide replacement, valve-seat refacing, and bottom-end inspection.

• Clutch and drivetrain: Hydraulic clutch service and bleeding, primary-drive and output-shaft work, transmission disassembly and assembly, and final-drive gear-contact, backlash, and preload checks.

• PGM-FI diagnosis: MIL codes and diagnostic flowcharts, fuel-pressure testing, pump and injector service, throttle-body checks, starter-valve synchronization checks, and ECM and sensor diagnosis.

• Lubrication and cooling: Oil-pressure testing, oil-pump inspection, cooling-system pressure tests, coolant replacement and air bleeding, and radiator, fan, water-pump, and thermostat service.

• Rune chassis: Front-wheel and bottom-link suspension work, axle alignment, steering-stem service, rear-wheel removal, and swingarm and suspension-linkage bearing replacement.

• Combined brakes: Master-cylinder and caliper disassembly, pad and disc inspection, separate lever- and pedal-circuit bleeding procedures, and proportional control valve removal and installation.

• Electrical and HISS: Charging and alternator tests, ignition and starter troubleshooting, lights/meters/switches service, key registration, immobilizer diagnosis, inner-lock-unit service, and wiring diagrams.

It is written for qualified professional technicians and assumes basic Honda motorcycle maintenance knowledge, shop training, special tools, and dedicated test equipment. Most sections pair service data and troubleshooting with detailed inspection and repair procedures.

In-Frame Work vs. Engine-Out Repair

The engine-removal chapter helps establish the teardown needed before work begins. Throttle bodies and injectors, the water pump and thermostat, cylinder heads and valves, clutch, most gearshift linkage, alternator, ignition pulse generator, and starter motor can be serviced in the frame.

Oil-pump work, primary gears and output shaft, transmission and gearshift-spindle service, and crankcase, piston, connecting-rod, and crankshaft work require engine removal. Transmission and bottom-end work also require crankcase separation.

Internal repair detail: Procedures include camshaft and cam-chain installation, color-code bearing selection, crankshaft installation, and crankcase sealing. The final-drive chapter adds shim selection, case-bearing replacement, and assembly checks.

PGM-FI, Regional Specifications, and HISS

The fuel chapter pairs component-location and system drawings with MIL fault trees and fail-safe information. It follows the tank, pump, injectors, throttle bodies, pressure regulator, fuel-pump relay, ECM, secondary-air system, and variable air-intake control, with checks for MAP/IAT, camshaft-position, knock, and vehicle-speed sensors.

Regional differences: GQ81B throttle bodies identify 49-state/Canada specifications; GQ81A identifies California specifications. California coverage adds EVAP canister and purge-solenoid procedures and hose routing. Idle and intake-cam data distinguish these regional versions; general specifications also distinguish the DA/EA/BA and DB/EB/BB overall-height groups.

Security diagnosis: HISS coverage includes the immobilizer/steering-lock interlock, diagnostic-code indication, and fault isolation. The ECM stores up to four key codes; if every registered key is lost, the ECM and transponder keys must be replaced.

Suspension and Combined-Brake Details

The chassis chapters distinguish suspension-linkage and pivot-bearing replacement from shock-absorber replacement as complete assemblies. Front-end service includes the axle-alignment checks required after fork-tube removal.

Brake documentation distinguishes the lever circuit from the pedal-operated combined circuit. The proportional control valve section covers removal and installation rather than internal overhaul.

Schematics, Tools, and Factory Reference Data

Illustrations include the Lubrication System Diagram, cooling-system System Flow Pattern, PGM-FI and HISS System Diagrams, Cable & Harness Routing, and the full Wiring Diagram. Exploded assembly views accompany the relevant service procedures.

Special-tool references include PGM-FI test harness set 07WMZ-MBGA000, SCS service connector 070PZ-ZY30100, cam-chain tensioner holders 07ZMG-MCAA300 and 07ZMG-MCAA400, final-drive assembly base 070MF-MEC0400, and HISS test harness 07AMZ-MECA100.

Reference tables cover component-specific torques, capacities, electrical test values, clearances, wear limits, and lubrication and sealant points.

Throttle-Body and Bearing Repair Cautions

Honda warns that commercial carburetor cleaner can damage the throttle bores’ molybdenum coating. Disturbing the white-painted throttle-body fasteners can cause throttle and idle synchronization failure.

Crankpin and main-journal bearing inserts are select-fit and color coded; incorrect oil clearance can cause major engine damage.

Fuel-system work calls for pressure relief with the ignition off and a well-ventilated, spark-free work area. The clutch and combined-brake chapters require fresh DOT 4 fluid, protection of painted, plastic, and rubber surfaces, and bleeding whenever a hydraulic circuit has been opened.

A Preview of Valve-Clearance and Oil-Pressure Data

Valve-clearance specifications are 0.15 ± 0.03 mm intake and 0.22 ± 0.03 mm exhaust, checked with the engine cold, below 35°C/95°F. The maintenance section also explains shim selection.

The lubrication chapter specifies oil pressure of 530 kPa (77 psi), measured at the oil-pressure-switch port at 5,000 rpm and 80°C/176°F, alongside the pressure-test procedure.