Yamaha YZ85W1 2007 Service Manual (P/N 5PA-28197-10)

This Yamaha factory service manual covers the 2007 Yamaha YZ85W1, model code 5PAG (USA). The U.S. edition carries P/N LIT-11616-20-08 and the Yamaha cover reference 5PA-28197-10.

Search, Bookmarks and Wiring Diagrams

Finding procedures and reading wire codes: Search the PDF text or use the chapter and section bookmarks to jump to a procedure. The small connector labels and wire codes in the monochrome diagram are easier to read when zoomed in.

The download is a single printable, English-language 248-page PDF, including the cover, front matter, and two wiring diagrams. The final two pages show the same ignition circuit in monochrome and color.

Engine Rebuilds, Chassis Service and Ignition Tests

These selected procedures highlight the main repair and diagnostic sections. The manual also covers spoke inspection and fuel petcock checks.

• Engine and transmission: Engine removal, top-end rebuilds, crankcase separation, crankshaft inspection, wet-clutch service, and transmission disassembly and reassembly.

• Carburetor and intake: Keihin PWK28 disassembly, float adjustment, reed valve inspection, and jetting charts for different track and weather conditions.

• Cooling system: Radiator and cap pressure testing, cooling-system leak checks, and service of the water-pump impeller, shaft, bearing, and seal.

• Brakes and steering: Front and rear master-cylinder and caliper repair, hydraulic brake bleeding, wheel-bearing service, and steering head bearing replacement.

• Suspension and final drive: Telescopic fork overhaul, rear-shock inspection and adjustment, swingarm linkage service, and drive-chain and sprocket checks.

• Electrical diagnosis: CDI ignition troubleshooting, coil resistance tests, engine stop switch continuity checks, wiring diagrams, and connector and cable-routing views.

Written primarily for Yamaha dealers and qualified mechanics, the manual assumes a basic understanding of mechanics and Yamaha repair techniques.

Piston Fit, Crankcase Work and Gearbox Inspection

The top-end section covers cylinder-head inspection and piston-ring checks. Its piston-to-cylinder matching chart pairs cylinder grades A–D with piston markings and colors, so you can identify the correct piston for the cylinder on the bench.

The crankcase section gives step-by-step instructions for splitting the cases and identifies Yamaha separating tool 90890-01135 / YU-1135-A. It warns that hammer blows can damage the gasket mating surfaces. Exploded assembly views identify lubrication points and parts that require replacement.

Clutch procedures distinguish the friction-plate types and show the pressure-plate alignment marks. The transmission section gives gear ratios, shows shift-fork orientation, and covers inspection of the shift drum, kick starter, and shift shaft.

Carburetor Settings and Race Maintenance

Jetting guidance links throttle opening, temperature, humidity, altitude, and track surface to carburetor setup. The symptom-based charts cover mixture problems and list alternative jets and needles with part numbers.

The race-based maintenance schedule covers air-filter service and lubrication. The manual also specifies the fuel premix and shows how to replace the silencer packing.

Radiator Testing and Water-Pump Service

Yamaha gives separate tests for radiator-cap opening pressure and cooling-system leaks. Water-pump repair covers drive-gear inspection and bearing installation, with a note on protecting the seal lip during shaft installation.

Brake Calipers, Forks and Rear Shock

The brake section warns that solvents can swell and distort the caliper piston seals. Fork overhaul covers damper rods, bushings, and oil seals. Suspension charts connect handling symptoms to damping, spring selection, and fork oil level.

The chassis specifications identify the semi-double cradle frame and link-type Monocross rear suspension. Rear-shock coverage is limited to removal, inspection, spring work, external adjustment, and replacement. Yamaha includes specific handling warnings for the nitrogen-charged shock and gas cylinder.

Tracing an Intermittent Spark

The ignition flowchart ties resistance and continuity checks to the wiring connections, helping isolate a no-spark or intermittent-spark fault before CDI-unit replacement. Connector views and wire codes help identify the relevant leads. The troubleshooting chapter also covers hard starting, poor running, shifting and clutch faults, overheating, and unstable handling.

Oil Capacities, Ignition Test Values and Torque Examples

The transmission oil table lists 0.50 L for a periodic oil change and 0.55 L as the total capacity.

For the CDI magneto pickup coil, Yamaha lists 248–372 ohms at 20°C (68°F) between the white/red and white/blue leads.

The engine and chassis torque tables give 79 Nm for the primary drive gear nut and 90 Nm for the rear wheel axle nut.