Yamaha QT 50 Maintenance Schedule

The "Periodic Maintenance / Lubrication Intervals" schedule is taken directly from a 1983 edition Yamaha QT50F factory service manual. Before starting any work, always consult the manual for your scooter's model & year and be sure you know what you're doing.

QT50 Periodic Maintenance / Lubrication Intervals




1 month
3 months
6 months
Thereafter every
6 months
Thereafter every
1 year
Cylinder head/exhaust system Decarbonize -   X X X  
Spark Plug Inspect/Clean or replace as required NGK BP4HS
.024" - .028" gap
X X X X  
Air filter Wash & dampen with oil Yamalube 2-cycle or SAE motor oil   X X X  
Carburetor Check operation, Clean/refit/adjust -     X   X
Brake system (complete)* Adjust free play. Replace shoes if needed Front EBC501, DP9109
Rear EBC501, DP9109
X X 3 months X  
Autolube Pump Check. Adjust and bleed air as needed. - X X X X  
Wheels & Tires* Front 18 psi, Rear 28 psi Front 2.00 X 14
Rear 2.25 X 14
X X X X  
Suspension system* Check operation. Repair as required - X X X X  
Battery* Top with distilled water. Check specific gravity and breather pipe. - X X X X  
Lights/Signals* Check operation. Replace bulbs as required. - X X X X  
Fittings/Fasteners* Tighten when needed - X X X X  
Transmission oil* Replace (warm engine before draining) 300cc SAE 10W30 type SE motor oil X check X X  
Control and meter cables* Apply lightly Lithium base grease     X X  
Brake lever Apply lightly Lithium based grease   X X X  
Brake cam shaft Apply lightly Lithium based grease   X X X  
Throttle grip and housing Apply lightly Lithium based grease     X X
Steering bearings Inspect thoroughly and pack moderately Lithium based grease    


2 years
Speedometer gear housing Apply grease lightly Lithium soap base grease         2 years
Wheel bearings Check bearings for smooth rotation Medium weight wheel bearing grease         X
Middle and final gear Check bearings for smooth rotation Lithium base wheel bearing grease         2 years

*Indicates pre-operation check items