2009 Yamaha YZ250FY Factory Service & Repair Manual (P/N LIT-11626-22-56)

• Document identity and exact coverage: A 275-page PDF of Yamaha's 2009 Owner's Service Manual for the YZ250FY in the U.S., Canada, Australia, and New Zealand and the YZ250F in Europe and South Africa. Cover identifiers are LIT-11626-22-56 and 5XC-28199-15; model codes are 5XCR (U.S./Canada), 5XCS (Europe), and 5XCU (Australia/New Zealand/South Africa).
• Four-stroke engine repair: Covers the Keihin FCR-MX37 carburetor, camshafts and timing system, cylinder head, valves and guides, piston and cylinder, clutch, water pump, balancer, and dry-sump lubrication system, with removal, disassembly, inspection, reassembly, and adjustment procedures.
• Bottom-end and transmission work: Details engine removal, crankcase separation, crankshaft inspection and installation, kick and shift shaft service, CDI magneto removal, and transmission, shift-cam, and shift-fork repair.
• Chassis and suspension service: Includes wheel and bearing work, front and rear brake disassembly and bleeding, front fork overhaul, steering and swingarm inspection, linkage maintenance, and rear-shock removal, bearing, spring, installation, and setup procedures.
• Electrical diagnosis: Provides the color-coded wiring diagram, electrical-component locations, ignition and throttle-position-sensor inspection charts, spark testing, coil and CDI-magneto checks, neutral-switch testing, and TPS replacement and adjustment.
• Factory reference data: Supplies maintenance schedules, component-specific torque tables, lubrication and cable-routing diagrams, fluid capacities, approved lubricants, wear limits, clearances, electrical test specifications, carburetor-setting data, suspension setup charts, and region-specific special-tool numbers.

Yamaha organizes removal and disassembly work around exploded views, job-order charts, inspection criteria, assembly notes, and final adjustments for the liquid-cooled DOHC four-stroke single. The service chapters expressly require basic knowledge and skill in Yamaha motorcycle servicing and caution inexperienced readers against relying on the manual alone. It is therefore suited to technicians and experienced owners with established workshop practice and the specified tools.

Engine, Drivetrain, and Fuel-System Procedures

The engine chapters follow the machine from the FCR-MX37 carburetor through the top end and into the crankcases. Carburetor coverage includes removal and disassembly, needle-valve and throttle-valve inspection, float-height measurement, accelerator-pump checks, reassembly, installation, and pump-timing adjustment. The valve-train material addresses camshaft timing, the automatic decompression system, cylinder-head inspection, valve and guide service, spring checks, and valve-clearance adjustment.

For major repair work, the manual continues through piston and cylinder inspection, clutch service, water-pump and oil-pump work, balancer timing, kickstarter and shift mechanisms, engine removal, crankcase splitting, crankshaft measurement and installation, and five-speed transmission inspection. Factory dimensions, service limits, tightening torques, lubrication points, capacities, and assembly data support those procedures.

Chassis, Electrical, and Race Setup

Chassis procedures cover spoke wheels, axles and bearings; front and rear calipers and master cylinders; brake-fluid replacement and bleeding; steering bearings; the swingarm and relay-arm linkage; and a full telescopic-fork rebuild. Fork service includes damper and base-valve removal, tube and bushing inspection, seal installation, oil filling, reassembly, and damping adjustment. Rear-shock coverage is narrower: removal, bearing and spring service, inspection, installation, preload, and damping setup are included, but Yamaha directs users not to disassemble the nitrogen-charged cylinder or reservoir.

Electrical fault finding is built around a complete wiring diagram and guided inspection paths. The ignition chart moves through spark, connections, the engine-stop switch, primary and secondary ignition-coil checks, CDI-magneto pickup and charging coils, the neutral switch, and the CDI unit. A separate TPS chart covers sensor resistance, input and output voltage, replacement, and adjustment. The manual also distinguishes the 5XC-R0 CDI unit for U.S./Canadian machines from the 5XC-S0 unit used in the other covered markets.

The tuning chapter is specific to motocross use. It relates atmospheric conditions and throttle opening to carburetor circuits, provides symptom-based jetting guidance, and identifies alternate jets and needles. Chassis setup covers final-drive selection, tire pressure, optional fork and shock springs, rider sag, damping, and front/rear symptom charts. Regional tables separate baseline gearing, carburetor calibration, suspension specifications, and other market-dependent settings before parts or adjustments are selected.

Tools, Diagrams, and Manual-Specific Cautions

Named service tools include the crankcase separator (YU-1135-A / 90890-01135), fork-seal driver (YM-A0948 / 90890-01502), dynamic spark tester or ignition checker (YM-34487 / 90890-06754), and pocket tester (YU-3112-C / 90890-03112). Visual references include the ignition/TPS wiring diagram, electrical-component location view, engine-lubrication diagrams, cable and hose routing drawings, assembly exploded views, and front/rear suspension troubleshooting charts.

The manual specifically warns against loosening the throttle-position-sensor screw unless the sensor is being replaced, because disturbing its setting can reduce engine performance. It also prohibits hammering the crankshaft during crankcase repair; the prescribed separating and installing tools are intended to prevent crankshaft damage. Safety coverage addresses gasoline, hot engine and exhaust parts, cooling-system pressure, hydraulic brake fluid, and the high-pressure nitrogen rear shock on this closed-course competition motorcycle.