2001–2006 Yamaha PW50(N) Service Manual (P/N 5PG-28199-80, -81, -83, -84 85)

• Six annual, trilingual manuals totaling 984 PDF pages: 164 pages each for 2001 PW50(N), 2002 PW50(P), 2003 PW50(R), 2004 PW50(S), 2005 PW50T1/PW50(T), and 2006 PW50(V).
• Explains the youth-specific START/RUN ignition control, throttle speed limiter, exhaust-port power reduction plate, pre-operation inspection, break-in, and adult-supervision rules.
• Covers scheduled maintenance plus spark-plug and air-filter service, throttle and idle adjustment, Autolube pump bleeding, cable synchronization and stroke adjustment, brake free play, and steering-head checks.
• Details Mikuni VM12SC carburetor removal, float and valve inspection, jet-circuit troubleshooting, muffler decarbonizing, and cylinder-head, cylinder, and piston service.
• Documents engine removal for wet centrifugal clutch disassembly and inspection, along with front and rear wheel removal, drum-brake inspection, tire and tube work, and rim checks.
• Supplies the ignition wiring diagram, fuel/compression/ignition troubleshooting chart, CDI-magneto and coil tests, component exploded views, and four cable-routing drawings.

This set contains Yamaha’s Owner’s Service Manual for each annual PW50 version, in English, French, and German. Yamaha presents these books as references for operation, features, basic maintenance, and inspection—not as full dealer workshop manuals. The content is best suited to a mechanically experienced adult responsible for a young rider, particularly someone comfortable using a dial gauge and electrical tester and prepared to follow Yamaha’s dealer referrals for work beyond the manuals’ basic-service scope.

Annual Model Codes and Publication Numbers

Confirmed printed publication numbers are 5PG-28199-80 (2001), 5PG-28199-81 (2002), 5PG-28199-83 (2004), 5PG-28199-84 (2005), and 5PG-28199-85 (2006). The PW50(R) title page is correct, but that PDF ends with a PW80(R) cover marked 3RV-28199-8C; that final-sheet number does not identify the PW50 manual.

The specification tables identify 5PG1/5PG2 for PW50(N), 5PG3/5PG4 for PW50(P), 5PG5/5PG6 for PW50(R), 5PG5/5PG6 again as printed in PW50(S), 5PG9/5PGA for PW50(T), and 5PGB/5PGC for PW50(V). These pair Canadian/Australian/New Zealand specifications with European/South African versions. The regional tables do not list a U.S.-market code, so U.S. machines should be matched by model and components before repair. Coverage is code-based rather than tied to a production serial range; identification pages show the frame or VIN location, engine number, and model label.

Factory Maintenance and Repair Depth

The schedule separates pre-ride checks from timed maintenance and lubrication. It covers the cylinder head and exhaust, spark plug, wet-foam air filter, carburetor, Autolube pump, brakes, wheels and tires, suspension, fuel cock, cables, bearings, fasteners, and transmission oil. Autolube work includes air bleeding, cable synchronization, and pump-stroke measurement.

Yamaha specifies a dial gauge (90890-03097; Canada YU-3097), Pocket Tester (90890-03112; Canada YU-3112-C), and ignition checker (90890-06754; Canada YM-34487).

For repair on the 49cc air-cooled two-stroke, the top-end chapter addresses head warpage, combustion-chamber and exhaust-port carbon, cylinder-bore condition, honing and rebore criteria, piston clearance, ring end gap, piston-pin bearing, and connecting-rod checks. The clutch chapter separates the frame from the engine before removing the right crankcase cover, housing, primary drive gear, and carrier; inspection data cover shoe lining and spring condition. Chassis procedures address wheel-installation alignment, brake shoe and drum limits, tire and tube reassembly, rim runout, and cable lubrication.

Ignition Diagnosis, Reference Views, and Scope Limits

Electrical fault isolation covers no or weak spark and an engine that starts but will not pick up speed. It includes switch-continuity, spark-gap, ignition-coil primary/secondary, and CDI-magneto pickup/charging/lighting-coil tests, backed by the system wiring diagram. The reference section supplies engine and chassis torque tables, fluid capacities and lubricant grades, wear limits, dimensional tolerances, carburetor calibration data, and electrical specifications.

Reference art includes a carburetor exploded view and removal photos, top-end views, a clutch-carrier exploded view, front and rear wheel exploded views, and full-machine cable-routing sheets.

The manual warns that hammering a stuck piston pin can damage the rod, piston, and bearing. It also cautions that careless carburetor changes can overheat or damage the engine, so tuning is tied to spark-plug evaluation.

This is not a full drivetrain overhaul manual: middle and final gear service is referred to the separate QT50F Service Manual P/N 3L8-28197-70, while crankshaft repair, steering-head disassembly, and wheel-bearing replacement are dealer-level referrals.

For this youth off-road motorcycle, observe the manual’s adult-supervision, single-rider, off-road-only, protective-gear, rider-weight, and pre-operation rules. Keep the speed limiter and power reduction plate in place until the supervising adult judges the rider ready, and verify every safety-critical repair before operation.