2009 Yamaha YFZ45RB / YFZ45RSEB Owner's Manual (P/N LIT-11616-22-75, LIT-11626-25-19)

This Yamaha YFZ450R set contains 542 pages across two PDF files. The 386-page 2009 YFZ450RY Service Manual, P/N LIT-11616-22-75 (first edition October 2008), covers U.S. model 18P1.

The companion 156-page YFZ45RB/YFZ45RSEB Owner’s Manual, P/N LIT-11626-25-19 (1st edition April 2011), covers operation, maintenance, and setup. The detailed workshop repair procedures belong to the 2009 service publication; the B/SEB book is an owner’s reference, not a later-model service supplement.

• Engine teardown and repair: engine removal, cylinder-head service, piston and ring inspection, crankcase separation, and crankshaft installation.
• Clutch and five-speed transmission sections cover friction-plate inspection and assembly, transmission-shaft disassembly, shift-fork and shift-drum checks, and gear-engagement inspection.
• Front and rear brake coverage includes caliper and master-cylinder overhaul, hydraulic-system bleeding, and parking-brake adjustment.
• Chassis repair procedures address rear-axle and hub bearings, swingarm and linkage service, front-arm ball-joint replacement, and steering toe-in adjustment.
• Fuel injection diagnosis combines fuel-pressure testing, fuel-pump and injector removal, throttle-body inspection, throttle-position sensor adjustment, and ECU fault-code troubleshooting.
• Cooling-system work includes radiator-cap and system pressure tests, radiator inspection, and water-pump impeller, seal, and bearing service.

Engine, Valvetrain, and Lubrication Service

The service manual covers the liquid-cooled, five-valve DOHC single with dry-sump lubrication, a wet multiple-disc clutch, and chain final drive. Valvetrain procedures detail camshaft timing, valve-pad selection, valve-guide replacement, and automatic decompression checks. Feed and scavenging oil-pump inspection is covered separately from routine oil and filter changes.

The procedures identify Yamaha special tools, including the crankcase separator YU-A9642 and universal clutch holder YM-91042.

ECU Diagnostics and Electrical Fault Tracing

The electrical chapters address ignition, starting, charging, lighting, and cooling-fan faults with system-specific circuit diagrams and component tests. ECU self-diagnosis includes fail-safe behavior, stored malfunction history, code erasure, and checks after repair.

The Sensor Operation Table supports diagnostic monitoring of throttle position, temperature, pressure, and other inputs. The Actuator Operation Table covers commanded tests of the injector, ignition coil, relays, and ISC idle-speed control valve. Yamaha’s FI diagnostic tool YU-03182 and TPS test harness YU-03204 are identified in the tool references.

Owner Maintenance, Bodywork, and Suspension Setup

The owner’s manual breaks down pre-operation checks and instrument functions for experienced off-road operators. Routine service covers spark-plug inspection and replacement, foam air-filter cleaning, and spark-arrester cleaning. Separate sections cover engine break-in and storage preparation.

Emission-control and general maintenance charts provide calendar-, mileage-, and hour-based service intervals. They identify work requiring dealer tools and skills and flag conditions that call for more frequent service.

Bodywork removal and installation includes separate YFZ45RB and YFZ45RSEB cowling-and-panel procedures for their different bolt and quick-fastener arrangements. This distinction matters when opening the vehicle for maintenance or rear spring-preload adjustment.

The double-wishbone front and linked swingarm rear suspension sections cover spring preload, rebound damping, and fast and slow compression damping adjustments. Shock service covers removal, inspection, external adjustment, and assembly replacement; internal damper rebuilding is outside its scope.

Factory Diagrams, Specifications, and Assembly Cautions

The 2009 YFZ450RY Wiring Diagram supports full-vehicle circuit tracing. The Engine Oil Lubrication Chart, Cooling System Diagrams, and Cable Routing views show oil flow and the placement of cooling lines, cables, and wiring. Exploded assembly views and job tables accompany component removal and installation sections.

Engine and chassis torque tables are backed by clearance specifications, wear limits, fluid capacities, tire-pressure specifications, and lubrication data. Electrical specifications provide resistance and voltage checks for individual components.

The camshaft section warns that uneven cap tightening can damage the cylinder head, camshaft caps, and camshafts. The rear-axle removal section flags direct hammer blows as a cause of damage to axle threads and splines.

Proper maintenance on these high-performance sport ATVs requires strict adherence to factory safety protocols, particularly when servicing hydraulic brakes or handling gas-charged shock absorbers.