2002–2008 Yamaha Grizzly YFM660F(P) ATV Service & Repair Manual FSM (P/N 5KM2-AE1, 5KM2-AE2)

• Factory document set: a 508-page PDF set — YFM660F(P) 2002 Service Manual 5KM2-AE1 (431 pages), YFM660FR Supplementary Service Manual 5KM2-AE2 (56 pages), and YFM660FS Supplementary Service Manual 5KM2-AE3 (21 pages).
• Covers engine removal and installation, camshaft and cylinder-head work, valve and piston inspection, crankcase separation, crankshaft and oil-pump service, plus radiator, thermostat, water-pump, and carburetor repair.
• Details the V-belt automatic transmission, primary and secondary sheaves, centrifugal clutch, chain-driven reverse gear, park mechanism, middle gear, front differential, CV joints, rear final drive, and gear-lash adjustment.
• Chassis procedures include wheel hubs and brake discs, pad replacement, master-cylinder and caliper service, hydraulic brake bleeding, steering-stem and knuckle work, tie rods, front and rear arms, shock absorbers, and toe-in adjustment.
• Electrical coverage uses ignition, electric-start, charging, lighting, signal, cooling-fan, and 2WD/4WD circuit diagrams, along with switch-continuity checks, fault-tracing charts, model-specific wiring diagrams, and cable, hose, and wire routing views.
• Provides exploded assembly drawings, job-order charts, component-specific torque tables, fluid and lubrication data, wear limits, clearances, electrical test specifications, and a factory special-tool list with Yamaha tool numbers.

Exact Model and Regional Coverage

The 2002 base manual covers YFM660F(P) model codes 5KM2 for Canada, 5KM3 for Europe, and 5KM4 for Oceania. The YFM660FR supplement adds 5KM9, 5KMB, and 5KMC for those regions, while the YFM660FS supplement identifies 5KMJ/5KMR, 5KMK/5KMS, and 5KML. These regional model codes are separate from the 5KM2-AE1, -AE2, and -AE3 manual numbers.

The supplements are change-only documents, not standalone repair manuals. Yamaha directs YFM660FR service back to 5KM2-AE1, and YFM660FS service requires both earlier publications. The base manual is the first edition issued in May 2001; the FR and FS supplements are first editions from June 2002 and April 2003. Yamaha produced this material primarily for its dealers and qualified mechanics, and it assumes a basic understanding of mechanical principles and machine-repair procedures.

Engine, CVT, and Shaft-Drive Repair

The engine chapters cover the 660 cm³ liquid-cooled SOHC single from external removal through the top end and into full internal repair. They cover rocker arms, camshaft timing and decompression components, valves and guides, cylinder and piston, recoil starter and AC magneto, balancer gears, oil-pump drive, crankcase bearings, crankshaft installation, transmission shafts, shift cam and forks, and middle-gear shim selection. Factory procedures are paired with inspection limits, fit and clearance data, lubrication points, and assembly-specific torque information.

V-belt drive work includes primary-sheave inspection, secondary-sheave disassembly and spring handling, wet centrifugal-clutch service, and final installation checks. The shaft-drive section goes well beyond basic fluid changes: it covers universal joints, front CV joints, the gear-motor-operated 2WD/4WD/Diff-Lock assembly, differential gear-lash measurement, rear CV-joint service, final-drive bearing removal, pinion and ring-gear positioning, shim selection, and backlash adjustment. Separate troubleshooting guidance helps distinguish wheel-bearing noise, incorrect gear lash, damaged gear teeth, and shaft-drive faults.

Chassis, Electrical, and Model-Specific Updates

Brake repair includes front and rear hydraulic components, pad and disc inspection, master-cylinder and caliper disassembly, hose routing, bleeding, and final checks. Steering and suspension chapters cover the handlebar and steering stem, bearing retainer, tie rods, ball joints, knuckles, stabilizer, control arms, wheel bearings, and shock absorbers. The periodic-service chapter adds valve-clearance and ignition-timing checks, compression testing, coolant replacement, V-belt inspection, shift-control adjustment, differential and final-drive oil service, battery testing, and headlight adjustment.

The YFM660FR supplement revises cable routing and service data and adds changed procedures for the starter cable, decompressor-equipped cylinder head, starter clutch, middle driven shaft, serviceable front differential, wheel hubs, knuckles, and rear suspension. The YFM660FS supplement adds the Diff-Lock override-switch function and diagnosis, revised carburetor, suspension, and CDI data, rear-brake-lever installation, switch testing, a signal-system circuit diagram, and a dedicated YFM660FS wiring diagram.

Factory Tools, Diagrams, and Repair Cautions

Named tools include the gear-lash measurement tool YM-01467 / 90890-01467, sheave spring compressor YM-04134 / 90890-04134, radiator cap tester YU-24460-01 / 90890-01325, and the FR supplement’s coupling-gear holding tool YM-01486 / 90890-01486. Diagram coverage includes coolant- and oil-flow layouts, exploded engine and driveline views, cable-routing plates, electrical circuit diagrams, troubleshooting charts, and full wiring diagrams.

The manual warns that insufficient gear lash can quickly destroy shaft-drive gear teeth after reassembly. It also identifies the middle driven-shaft bearing retainer as left-hand threaded; treating it like a conventional fastener can damage the retainer or shaft threads. Many procedures require the ATV to be securely supported and involve fuel, coolant, brake fluid, batteries, or spring-loaded drive components, so proper lifting equipment and the manual’s safety precautions are required before repair work begins.