Honda ZB50
The ZB50 is a 50 cc (3.1 cu in) motorcycle produced by Honda belonging to its Z Series family of mini bikes. The ZB50 is very similar to the Monkey-R and Monkey-RT which were marketed only in Japan in 1987 and 1988.
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| Manufacturer | Honda |
|---|---|
| Production | 1987–1988 (1988 U.S., Canada, Western-Europe) |
| Class | Standard |
| Engine | 49 cc (3.0 cu in), SOHC, 2-valve, four-stroke, air-cooled, single |
| Power | 2.6 PS (1.9 kW; 2.6 hp) |
| Transmission | 3-speed semi-automatic |
| Suspension | Front: telescopic Rear: swingarm |
| Brakes | Front: drum Rear: drum |
| Tires | Front: 3.50-10 2PR Rear: 3.50-10 2PR |
| Rake, trail | Rake: 25 degrees Trail: 64 mm |
| Wheelbase | 1,065 mm (41.9 in) |
| Dimensions | L: 1,500 mm (59 in) W: 620 mm (24 in) H: 910 mm (36 in) |
| Seat height | 660 mm (26 in) |
| Weight | 71 kg (157 lb) (dry) |
| Fuel capacity | 7 l (1.5 imp gal; 1.8 US gal) |
| Related | Honda Z series |
The ZB50 was available in 1988 in the United States, Canada and western Europe. Only 3058 were produced for the US market as the bike proved too expensive to mass-produce. The ZB50 was offered as a street and trail alternative to the Z50R, which was geared more towards dirt-track riders. The ZB50 is characterized by a perimeter twin spar frame, giving it the appearance of a miniature sportbike.
Specifications
| Total length | 1,500 mm (59 in) |
|---|---|
| Total width | 620 mm (24 in) |
| Total height | 910 mm (36 in) |
| Wheelbase | 1,065 mm (41.9 in) |
| Dry Weight | 71 kg (157 lb) |
| Engine type | Air-cooled 4-cycle SOHC single-cylinder |
| Displacement | 49 cc (3.0 cu in) |
| Compression ratio | 10.0:1 |
| Bore x Stroke | 39.0 mm x 41.4 mm |
| Max Power output | 2.6 PS (2.6 hp) |
| Max Torque | 4.7 N⋅m (3.5 ft⋅lbf) at 4500 rpm |
| Max speed | 50 km/h (31 mph) |
| Carburetor type | Keihin PB 12, 13 mm piston-valve carburetor, with a butterfly style manual choke |
| Lubrication | Forced and wet sump |
| Fuel tank capacity | 7 L (1.8 US gal) |
| Reserve capacity | 1 L (0.26 US gal) |
| Load Capacity | 74 kg (163 lb) |
| Clutch | Wet multi-plate, operated both by centrifugal action and by gear-lever. |
| Transmission type | 3-speed |
| Gear ratios | 1st: 3.272, 2nd: 1.823, 3rd: 1.190 |
| Reduction gear ratio | Primary: 4.058, Secondary: 2.600 |
| Starter | Kick |
| Ignition | Capacitor Discharge Ignition (CDI Magneto) system |
| Front Suspension | Telescopic Fork |
| Rear Suspension | Swing arm |
| Tire sizes (F/R) | 3.50-10 2PR / 3.50-10 2PR |
| Front Brake | Drum, cable operated |
| Rear Brake | Drum, rod operated |
| Frame type | Twin spar perimeter |
Model information
The ZB50 is a street legal motorcycle, powered by a 4-stroke 49 cc overhead cam engine. Unlike the Z50R, the ZB50 engine features a roller bearing camshaft, an automatic cam chain tensioner, and a NGK CR6HS spark plug.[1]
The electrical system is 12 volt and the ignition is a solid state electronic CDI.[1]
The carburetor has stock settings of 1-3/4 turns out for the air screw, the jet needle is set at the 3rd groove from the top, the float level is 18 mm, and it has a #75 main jet.[1]
The transmission is 3-speed constant mesh, with a 3-up shift pattern, it uses a wet multi-plate centrifugal clutch, with the following gear ratios: 1st 3.272, 2nd 1.823, and 3rd 1.190. It has a primary reduction ratio of: 4.058, and a secondary reduction ratio of 2.6 via the chain drive (15 tooth front sprocket and 39 tooth rear sprocket).[1]
Canadian and U.S. versions differ by the speedometer units, where Canadian speedometers use metric units, and U.S. speedometers use English units [1] The Western-Europe versions differ, accordingly to the country they are meant for with -headlight -headlight brackets -fenders -tail -plateholder(Netherlands)
References
1. 1988 Honda ZB50 Service Manual

