2004-2009 Honda TRX 450R / TRX450ER Service Manual

Built for professional technicians and serious DIYers, this original OEM publication provides 523 pages of factory-level maintenance and assembly standards for the 2004–2009 Honda TRX 450R and TRX 450ER Sportrax. It fully covers both the kickstart and electric-start variants.

Whether you are running a busy workshop or rebuilding your quad in the garage, this digital reference is built for speed and accuracy.

Deep Technical Coverage & Specifications

This factory workshop documentation ensures accurate part replacement and assembly without the guesswork. It dives deep into the mechanical and electrical systems of the entire TRX450 generation, featuring dedicated sections for the updated engine and electrical specifications introduced from 2006 onward.

• Visual References: 47 exploded-view diagrams, 16 comprehensive wiring harness and cable routing schematics, and 28 detailed torque specification tables.
• Engine & Valvetrain: Precise data for the Unicam setup, including intake and exhaust valve clearances (e.g., 0.16 ± 0.03 mm for intake), cam lobe heights, and valve spring free lengths. Cylinder head bolt torque is specified clearly at 54 Nm (40 lbf-ft).
• Lubrication System: Complete specifications for the twin-sump setup. This documents oil capacities for both the engine and transmission (such as the 0.55-liter transmission capacity for 04-05 models), pump rotor tolerances, and seal point requirements.
• Electrical Data: Accurate peak voltage values for ignition coils, exciter coils, and alternator outputs covering both starting systems.
• Chassis & Body: Clear procedural breakdowns for frame and body assembly, including seat, fender, and exhaust routing.

Working on high-performance ATVs requires precision. Always adhere to standard workshop safety protocols and consult a certified technician before undertaking major engine or chassis work on this equipment.