2007–2012 Yamaha PW50W / PW50 OEM Service Manual (P/N LIT-11616-20-15)

This Yamaha factory service manual covers the 2007–2012 PW50W and European-market PW50 minibikes with air-cooled, reed-valve two-stroke engines. The first edition, May 2006, carries P/N LIT-11616-20-15 and cover reference 5PG-28197-10. Model codes are 5PGD outside Europe and 5PGE for Europe.

Search, bookmarks, and diagram detail: The PDF has searchable text and bookmarks for chapters, individual procedures, and the appended wiring diagrams. The external “Back to Index” link points to a separate file that is not included. Small wiring labels are clear when enlarged.

• Engine repair: Engine removal and installation, cylinder-head resurfacing, piston and ring inspection, reed-valve service, crankcase separation, and crankshaft checks.

• Lubrication and fuel: Autolube pump removal and installation, minimum-stroke adjustment, air bleeding, and Mikuni VM12SC carburetor disassembly, inspection, and reassembly.

• Clutch and final drive: Centrifugal clutch inspection, kick starter service, middle-gear repair, and shaft-drive disassembly and reassembly.

• Chassis and brakes: Front and rear drum-brake service, steering-head bearing replacement, left fork-leg disassembly, and rear shock absorber and swingarm inspection.

• Electrical diagnosis: CDI magneto service, ignition troubleshooting charts, switch-continuity checks, coil resistance tests, and wiring and circuit diagrams.

• Service references: Periodic maintenance and general lubrication charts, cable-routing views, exploded assembly drawings, component torque tables, fluid capacities, and wear limits.

Yamaha wrote this manual primarily for its dealers and qualified mechanics, and it assumes a basic understanding of mechanics and the repair techniques these vehicles require.

Engine and Drive Repair

Cylinder and piston measurements are paired with inspection limits and replacement criteria. The engine sections also cover piston-ring installation, cylinder-head assembly, and crankshaft runout and bearing checks. Reed-valve inspection addresses valve bending and stopper height, with intake manifold removal and installation.

Clutch repair covers the primary drive and primary driven gears, clutch housing, centrifugal clutch shoes, and springs. The middle-gear section details the main axle assembly, driven pinion, and shims. It identifies the retaining screw's left-hand thread and the required hexagon wrench, 90890-01306 / YM-01306.

Shaft-drive procedures include drive-pinion and ring-gear inspection, bearing checks, lubrication, and rear-arm installation.

Autolube and Carburetor Service

The Autolube section covers the oil pump drive gear, seals, and cable adjustment. Minimum-stroke measurement uses dial gauge and stand set 90890-01252; the pump installation instructions also refer to air bleeding and stroke adjustment.

Carburetor procedures address the float chamber, needle valve, jets, starter plunger, and throttle valve, including float-height inspection. Related maintenance covers throttle-cable free play, engine idle, air-filter service, and spark-arrester and exhaust-chamber cleaning.

Forks, Steering, and Drum Brakes

Fork disassembly and reassembly apply only to the left front fork leg; Yamaha explicitly says not to disassemble the right leg. Rear shock absorber coverage addresses removal, inspection, and replacement, while swingarm service includes bearing inspection.

Brake shoe measurement drawings accompany lining-thickness and brake-drum inspection. Steering-head procedures cover bearing and race replacement and adjustment. The manual warns that incorrect bearing-race installation can damage the steering-head pipe.

Securely support the vehicle on a proper stand to prevent it from falling over, and follow the manual's precautions for fluids, spring-loaded parts, and ignition testing.

Ignition Diagnosis and Wiring

Electrical coverage includes the stator assembly, ignition coil, pickup and charge coils, lighting coil, control unit, and ignition control switch. The no-spark and intermittent-spark troubleshooting charts help narrow down the fault before CDI-unit replacement, with connector views and a control-unit resistance matrix supporting the tests.

The Ignition System Circuit Diagram and cable-routing views show circuit connections and harness placement. Factory specifications include electrical test values and fixed ignition-timing data. Testing cautions explain how inserting probes into coupler terminal slots can loosen or damage the leads.

PDF Manual and Wiring Diagram Sheets

One printable English PDF contains 168 pages total: the 166-page manual, including its covers, front matter, and blank pages, followed by two appended wiring-diagram sheets, one black-and-white and one color. Both sheets are already included in the total.