Honda TRX500FA/FGA Rubicon ATV Service Manual, 2005–2008

This Honda service manual covers the 2005–2008 TRX500FA and TRX500FGA Rubicon ATVs. It includes Standard and GPScape service information and specifications for U.S., Canadian, and U-type models. The manual carries a November 2004 issue date.

PDF Search, Bookmarks, and Wiring Detail

Text search and page navigation: The main service text is searchable. Labels inside the wiring-diagram images are outside the text search, and some small connector markings and wire-color codes remain difficult to read even when enlarged. The 540 embedded bookmarks are numbered by page.

The download contains one printable English-language PDF with 541 pages. The total includes 521 service and reference pages, one cover, three blank preliminary pages, and 16 memo pages.

Engine Service, Hondamatic Diagnostics, and Chassis Repair

These selected service topics show the range of the manual. It also includes spark arrester cleaning and fuel-level sensor testing.

• Engine and scheduled maintenance. Maintenance schedules, step-by-step valve clearance adjustment, engine removal and installation, cylinder head and camshaft service, piston inspection, and crankshaft and balancer service.
• Fuel and lubrication. VE-type carburetor overhaul, starting-enrichment valve inspection, pilot screw adjustment, oil-pressure testing, and oil pump and oil cooler service.
• Cooling system. Cooling-system pressure testing, thermostat inspection, coolant replacement and air bleeding, and water pump removal and installation.
• Hondamatic and sub-transmission. Centrifugal clutch service, Drive/Low/Reverse gear inspection, gearshift linkage adjustment, control-system troubleshooting, and the Hondamatic initial setting procedure.
• Driveline and chassis. Front differential and rear final-drive service, steering and suspension repair, hydraulic front disc brake service, and mechanical rear drum brake service.
• Electrical and 4WD diagnosis. Alternator and starter clutch service, charging and ignition tests, electric starter repair, lights, meters and switches, selectable 4WD diagnosis, and GPScape receiver troubleshooting.
• Workshop references. Factory torque tables, lubricant requirements, wear limits, electrical test specifications, cable and harness routing drawings, and problem-code blink charts.

Honda wrote this manual for qualified service technicians with the training, tools, and equipment needed for the procedures.

Engine, Carburetor, and Cooling Service

Top-end service. The cylinder head, camshaft, cylinder, and piston can be serviced with the engine in the frame. The manual covers valve guide replacement and valve seat refacing, with inspection limits for the rocker arms, cam followers, cylinder, piston, and rings.

Cylinder head cover installation. The reassembly instructions show the tightening sequence and explain how to seat the rocker arm followers on the pushrod ends. Tightening the cover with those parts misaligned can cause severe engine damage.

Carburetor identification. A and CM models use the VE6AE carburetor, while U models use the VE6AF. The fuel section covers the vacuum piston and diaphragm, primer mechanism, float inspection, and U-type air cut-off valve. Emissions diagrams show how the related components are routed.

Cooling-system checks. Coolant-flow diagrams accompany leak testing and circulation-system service. Honda explains that coolant with silicate inhibitors can wear the water pump seals prematurely or block radiator passages.

Hondamatic Diagnostics and Driveline Repair

Transmission controls. Fault charts, circuit diagrams, and connector views help technicians trace a shift problem through the control motor, angle sensor, throttle position sensor, switches, and wiring before removing the transmission. The chapter also covers code retrieval and clearing, fail-safe operation, and initial setting after specified ECM, sensor, or throttle-system work.

Automatic transmission and sub-transmission. Honda specifies replacing a faulty automatic transmission unit as an assembly. Removal requires taking the engine out of the frame and separating the crankcase. The separate sub-transmission chapter covers inspection of the gears, bushings, shift forks, and shift drum.

Differential and final drive. The front and rear driveline chapters show how to select shims, measure backlash, and check gear-tooth contact patterns. Front differential service includes a limited-slip torque check with tool 07KMK-HC50101 or the U.S. tool 07KMK-HC5010A.

Suspension, Brakes, and Electrical Testing

Chassis service. Procedures cover knuckle bearings, suspension-arm ball joints, steering-shaft bearings, swingarm pivots, and hydraulic front brake bleeding. The shock-absorber instructions distinguish the lower pivot bearings on 2005–2006 models from the bushings used after 2006.

Wiring and selectable 4WD. Separate diagrams distinguish Standard and GPScape configurations and show regional and production differences. The electrical sections cover charging faults, ignition peak-voltage tests, starter motor inspection, and 4WD faults involving the vehicle speed sensors and front final clutch.

GPScape receiver. The diagnostic procedures distinguish communication faults from slow position acquisition and cover receiver power, ground, and backup voltage checks.

Compression, Idle Speed, and Coolant Specifications

• Cylinder compression: 608–902 kPa at 450 rpm with the engine warm, the transmission in neutral, and the throttle fully open.
• Engine idle speed: 1,400 ± 100 rpm with the engine warm and the transmission in neutral.
• Coolant capacity: 1.7 liters for the radiator and engine, plus a separate 0.40-liter reserve tank capacity.