The Yamaha BW is an air-cooled two-stroke scooter that Yamaha has sold under several names, including the Zuma in the United States and the MBK Booster in Europe. It first appeared in 1989 and stayed in production for more than two decades.
Yamaha BW at a glance
| Maker | Yamaha Motor Company |
|---|---|
| Class | Air-cooled two-stroke scooter |
| Also sold as | Zuma, MBK Booster |
| First models | 1989 |
| Carburettor | 14 mm Teikei with automatic choke |
| Induction | reed valve |
| Cooling | fan-assisted |
| Starting | electric with backup kick start |
| Tyres | 120/90-10 front, 130/90-10 rear |
| Front brake | 155 mm hydraulic disc (drum before 1998) |
| Fuel economy | up to 123 mpg-US according to the EPA |
| Later versions | Zuma 125 (2011) and Zuma 50F (2012) |
Based on one source (English Wikipedia). The article describes the BW as sold in the United States as the Zuma.
History of the Yamaha BW
The BW was designed as a simple, tough small scooter. Its 14 mm Teikei carburettor has an automatic choke and reed-valve induction, and cooling is assisted by a fan. Oil is fed automatically from a separate tank with a low-level light on the instrument panel. The scooter has electric starting with a kick-start backup, five-spoke cast wheels and a dual seat with room for a full-face helmet.
The chassis is modest but practical. The front fork has 66 mm of travel and the rear shock 61 mm. Brakes are a 155 mm hydraulic front disc and a rear drum, although scooters built before 1998 had a front drum. The rear cargo rack doubles as a passenger grab rail. From 2001 the Zuma was given twin “bug-eyed” headlights, one wired to low beam and the other to high beam.
Yamaha withdrew the Zuma from the United States in 2006 and 2007, then brought it back for 2008–2011 with slightly higher gearing. In 2011 came the four-stroke, fuel-injected Zuma 125, and in 2012 the Zuma 50F replaced the two-stroke 50. Model codes follow Yamaha’s system: CW for the 1989–1990 and 1997–2001 scooters, YW after 2001, with letters marking the model year.
Design and features
- Autolube oil injection: no premixed fuel, with a warning light when the oil runs low.
- Practical body: a helmet-sized compartment under the seat and a rear rack for luggage.
- Simple brakes: a single front disc from 1998, drum brakes on earlier scooters.
- Long life: the same basic scooter was sold as the Zuma and Booster for over twenty years.
Yamaha BW versions
- BW 50 two-stroke: the original air-cooled 49 cc scooter.
- Zuma (United States): the American name, with twin headlights from 2001.
- MBK Booster (Europe): the French-market version of the same scooter.
- Zuma 125 (2011): four-stroke, fuel-injected model.
- Zuma 50F (2012): four-stroke replacement for the two-stroke 50.
The BW sits alongside the Jog and the Aerox in Yamaha’s scooter range. More models are in the Yamaha collection.
Sources
- Yamaha BW, English Wikipedia: design, equipment, model codes, market history
