Honda TRX450R / TRX450 ATV 2004–2005 Parts Catalog (P/N 61HP101)

This 453-page PDF set combines the 2004-2005 Honda TRX450R Service Manual with the American Honda TRX450R'04 Parts Catalog. Honda states that the service manual is written for people with basic maintenance knowledge of Honda motorcycles, motor scooters, or ATVs; deeper engine, brake, and electrical repair also assumes the specified measuring equipment and special tools.

• Coverage and document scope: 333-page service manual for the 2004-2005 TRX450R, plus a 120-page OEM parts catalog for the 2004 TRX450R only. The parts catalog is the November 2003 paper edition, P/N 14HP14E1P.
• Engine work covers removal and installation, cylinder-head disassembly, valve-guide replacement and valve-seat refacing, camshaft/decompressor setup, cylinder and piston service, clutch and kickstarter repair, crankcase separation, transmission inspection, crankshaft service, and balancer assembly.
• Fuel, lubrication, and cooling sections detail carburetor removal, teardown, assembly, and pilot-screw adjustment; oil-pump, strainer, pressure-relief-valve, and oil-cooler service; cooling-system testing, coolant replacement and air bleeding, thermostat checks, and water-pump mechanical-seal replacement.
• Chassis procedures include front and rear wheel service, tire removal and repair, hub and bearing replacement, rear-axle and bearing-holder work, shock and linkage inspection, swingarm service, suspension-arm bearing replacement, steering-shaft service, and tie-rod adjustment.
• Brake and electrical coverage includes fluid replacement and bleeding, master-cylinder and caliper overhaul, pad and disc inspection, alternator and regulator tests, ignition peak-voltage diagnosis, ignition timing checks, throttle-position-sensor testing, and cooling-fan and ECT-sensor diagnosis.
• Diagnostic references include the TRX450R wiring diagram, cable-and-harness routing views, Unicam and twin-sump system illustrations, the lubrication-system diagram, and factory troubleshooting charts for hard starting, loss of power, poor low- or high-speed performance, and handling faults.

Factory Repair Depth

The engine chapters go well beyond routine tune-up information. They provide compression testing, valve-clearance and decompressor inspection, shim selection, cam timing, cylinder-head overhaul, piston and ring inspection, clutch disassembly, transmission and shift-fork checks, crankshaft inspection, crankcase bearing replacement, and final reassembly data. Specifications are organized by system and include component-specific torque tables, fluid and lubrication data, clearances, wear limits, and service limits.

Technical-feature pages explain Honda's Unicam valve train, separate engine and transmission oil chambers in the twin-sump lubrication system, and the hot-start circuit. Routine service coverage extends to the maintenance schedule, air-cleaner service, engine and transmission oil, radiator and drive-chain care, brake inspection, clutch and parking-brake adjustment, suspension checks, tires, and steering alignment.

OEM Parts Identification

The separate parts catalog applies to TRX450R'04 Area Code A machines beginning with engine serial TE30E-8000001 and frame/VIN *478TE3004A000001; it identifies carburetor type QA16A A**. Each exploded assembly is paired with reference numbers, descriptions, quantities, OEM part numbers, H/C entries, and serial-number columns. Engine plates cover the cylinder head, camshaft and valves, cam-chain tensioner, clutch, oil and water pumps, crankcase, crankshaft and piston, balancer, transmission, shift drum, kickstarter, and carburetor. Frame plates include brakes, steering, front and rear suspension, rear axle and drive chain, fuel tank, bodywork, exhaust, wire harness, oil cooler, and radiator. Master, part-number, and description indexes help trace a component back to its plate.

This catalog does not provide 2005 OEM parts listings; its serial and ordering data are specific to the 2004 model. The 2005 coverage in this set comes from the service manual's repair procedures.

Special Tools and Repair Cautions

Honda tool references include the cam-chain tensioner holder 07ZMG-MCAA400, clutch-center holder 07724-0050002, flywheel puller 070MC-HP10100, IgnitionMate peak-voltage tester MTP07-0286, and ATV Bead Buster KLS379024, along with bearing drivers, pullers, valve-seat cutters, and cooling-system test equipment.

Two assembly cautions are especially important: the oil filter is directional, and installing it backward can cause severe engine damage; the ignition control module can be damaged by impact or by disconnecting its connector while current is flowing. Brake and suspension work is safety-critical; the manual calls for contaminated pads to be discarded and the ATV to be securely supported before wheel or suspension repair.