The "Periodic Maintenance / Lubrication Intervals" schedule is taken directly from a 1981 edition Honda NU50/NU50M Urban Express Factory Service Manual, which covers the 1982 Urban Express. This maintenance schedule is based upon average riding conditions. Machines subjected to severe use, or ridden in unusually dusty areas, will require more frequent servicing. Before starting any work, always consult the manual for your scooter's model & year and be sure you know what you're doing.

NU50/M Periodic Maintenance / Lubrication Intervals

I: Inspect   R: Replace    C: Clean    L: Lubricate   A: Adjust

Item

Type

Pre-Ride Inspection

 Initial safety inspection
 1 month or 200 mi (300 km)		 Thereafter every
12 months or 1000 mi
(1500 km)

 Thereafter every
 24 months or 2000 mi (3000 km)		 Thereafter every
 24 months or 2000 mi (3000 km)
Air filter element Clean in solvent, then lightly soak in 10W30 motor oil     Change every 6 months
Carburetor

Idle speed is 1400 rpm

   I I I I
*Throttle operation 3/8-5/8" (10-15mm) free play   I I I I
Oil pump Adjust after the throttle cable has been adjusted.     I I I
Fuel filter screen Located under the petcock   C C C  
Fuel line Replace any parts which show deterioration, damage, or leakage   I I I  
*Oil and fuel level Check   I      
Decarbonize cylinder head, cylinder, piston, and muffler           C
Transmission oil Drain bolt is on bottom LH side of engine case. Fill through check bolt, located to the right and above the drain bolt. 90cc (3.0 oz) of 90wt gear oil   R   R
*Transmission case for leaks Inspect

 

I

 

  

 
Clutch shoe wear        

 

I
*Tires and tire pressure Check for wear, cracks, or damage

18 psi Front, 24 psi Rear
Tire size: 2.25 x 16

I

 

  

 
Wheel trueness and spokes       I I I
*Brake operation and free play 3/8-5/8" (10-15mm) free play  

I

I

 I I
Brake linings Front & Rear: EBC333     I I  
Steering head bearings Check for free rotation. Adjust steering head nut as needed.   I   I  
Suspension operation Check for smooth operation and signs of damage.    

I

I

 
Nuts and bolts Torque to proper value as needed    

I

I

 
Spark plug 0.024-0.028" (0.6 - 0.7mm) gap NGK BR8HS (BR9HS - colder, BR7HS - hotter)     R  
*Battery fluid level   Distilled water I      
Battery fluid specific gravity   YB2.5L-C-1, CB2.5L-C-1   I I  
All lights and horn    

I

      

* These are simple to perform and may be serviced by the owner. Other maintenance items should be serviced by an authorized Honda dealer, unless the owner has the proper tools, service data and mechanical knowledge to do the work.