Yamaha PW50(P) 2001 Owner's Service Manual (P/N 5PG-28199-81)

Yamaha’s 2001 PW50(P) Owner’s Service Manual (P/N 5PG-28199-81) covers model code 5PG3 for Canada, Australia, and New Zealand and 5PG4 for Europe and South Africa. The April 2001 printing covers operation, scheduled maintenance, inspection, and minor repairs.

PDF Search, Bookmarks, and Wiring Detail

Finding procedures and reading the wiring diagram — The service text cannot be searched in the PDF. Embedded bookmarks lead to the cover or contents pages, which list the printed page numbers. Small wire-color codes and connector labels in the CDI wiring diagram are readable when zoomed in.

One printable 161-page PDF contains the English, French, and German text. The total includes the front and back covers and five memo pages.

Riding Setup, Two-Stroke Service, and CDI Diagnosis

These selected highlights focus on common service jobs. The manual also covers cleaning and long-term storage.

• Riding setup and maintenance — Operating controls, pre-ride inspections, engine break-in, and a maintenance and lubrication schedule for the engine and chassis.
• Carburetor, exhaust, and Autolube — Carburetor removal and inspection, jetting by throttle range, exhaust decarbonizing, and oil pump bleeding and adjustment.
• Top-end service — Cylinder-head, cylinder, and piston removal, with bore and piston measurements, ring checks, and piston-pin bearing and connecting-rod inspection.
• Centrifugal clutch — Engine removal for clutch access, an exploded assembly view, disassembly, and inspection of the clutch shoes and springs.
• Wheels, brakes, and steering — Front and rear wheel removal and installation, drum brake inspection, tube-type tire repair, and steering-head adjustment.
• Fault finding and ignition — A fuel, compression, and ignition troubleshooting chart, plus a CDI wiring diagram, spark-gap testing, and electrical checks.

The owner sections explain basic operation and routine care, while the minor-repair sections are suited to experienced owners and technicians who can work from Yamaha’s measurements and test specifications.

Model Identification and First-Ride Checks

The identification section shows where to find the frame or engine serial number, market-specific VIN, and model label for parts ordering. The controls section explains the ignition control switch, fuel cock, choke, kick starter, and both hand-operated brake levers.

Yamaha explains how the throttle speed limiter and exhaust power reduction plate let a parent match the machine’s output to a beginning rider’s skills. The pre-ride checklist covers fuel, engine and transmission oil, brakes, tires, controls, and fasteners. The maintenance schedule also covers the spark plug and wet-element air filter.

Carburetor, Autolube, and Top-End Detail

The Mikuni VM12SC carburetor section covers fuel-passage cleaning and float and float-valve inspection. Yamaha explains how the jet needle, pilot circuit, throttle slide, and main jet affect different throttle ranges, and how altitude, temperature, humidity, and heavy loads affect carburetion.

The Autolube section explains how to synchronize the pump cable with the throttle and check minimum pump stroke. Yamaha lists dial gauge 90890-03097 / YU-3097 for this adjustment. The muffler section covers carbon removal from the exhaust pipe and silencer and inspection of the muffler gasket.

The top-end section covers combustion-chamber and exhaust-port deposits, cylinder-head warpage, and when light honing is appropriate. It also gives piston clearance, ring end gap, connecting-rod play, and crankshaft dimensions. Reassembly notes cover ring seating and break-in. Yamaha warns that hammering out a stuck piston pin can damage the rod, piston, and bearing, and refers crankshaft repair to a dealer.

Clutch and Chassis Inspection

The clutch procedure starts with rear-arm and engine removal. The disassembly sequence identifies the oil pump, carburetor, CDI magneto lead, right crankcase cover, primary gears, clutch housing, and carrier. The exploded view identifies the dampers, weight shafts, and springs, and the inspection section gives lining and spring limits. The crankcase, middle and final drive, and front fork are covered through specifications and related service checks.

The front and rear wheel exploded views accompany the removal and installation procedures. The chassis section explains how to measure brake shoe wear and rim runout, inspect brake drums, refit tires and tubes, and lubricate cables. Yamaha refers wheel-bearing replacement and steering-head disassembly to a dealer.

CDI Wiring and Troubleshooting

The troubleshooting chart helps narrow hard starting or loss of power to fuel supply, compression, or ignition. The electrical section goes further with checks for weak or absent spark and for an engine that starts but fails to pick up speed.

The component-location drawing and wire-color legend help trace the ignition control switch, ignition coil, control unit, diode, CDI unit, magneto, spark plug, and ground. Test procedures cover switch continuity, ignition-coil resistance, and pickup, charging, and lighting coils. Yamaha lists the Pocket Tester 90890-03112 / YU-3112-C and Ignition Checker 90890-06754 / Dynamic Spark Tester YM-34487. Separate cable-routing drawings and component-specific torque tables support reassembly.

Support the machine securely during wheel or steering work, keep sparks and open flames away from fuel-system checks, and let the exhaust cool before service. Yamaha also cautions that incorrect carburetor settings can damage the engine.

Autolube Stroke and Clutch Wear Limits

The Autolube adjustment table specifies a minimum pump stroke of 0.25–0.30 mm (0.010–0.012 in) and a maximum stroke of 1.00–1.15 mm (0.039–0.045 in).

For the centrifugal clutch shoes, Yamaha lists a standard lining thickness of 1.0 mm (0.040 in) and a wear limit of 0.7 mm (0.028 in).