Yamaha Zuma

Yamaha Zuma

Manufacturer	Yamaha
Also called	BWs, MBK Booster
Production	2002-2005, 2008-2009
Class	Scooter
Engine	Horizontal Minarelli 49 cc air-cooled (in 2011 Yamaha introduced a 125 cc engine to the Zuma model), carbureted 2-stroke, electronic ignition Bore x stroke: 40.0 mm x 39.2 mm Compression ratio: 7.0:1
Top speed	42 mph (68 km/h)
Transmission	V-belt automatic
Suspension	Front: Telescopic fork Rear: Single shock
Brakes	Front: 115mm disc Rear: drum
Tires	Front: 120/90-10 Rear 130/90-10
Wheelbase	50.2 in (1,275 mm)
Dimensions	L: 74.4 in (1,890 mm) W: 27.8 in (706 mm) H: 43.7 in (1,110 mm)
Seat height	30.1 in (765 mm)
Fuel capacity	1.5 US gallons (5.7 L)
Fuel consumption	123 mpg‑US (1.91 L/100 km)
Related	Yamaha Zuma 125

The Zuma is an air-cooled 49 cc two-stroke scooter made by Yamaha Motor Company. It is also marketed as the Yamaha BWs, and the MBK Booster.

Model information

Yamaha numbers its scooter models according to their make (in the case of the Zuma, all models numbers begin with the letters YW), the engine size (given in approximate cubic centimeters— the Zuma's usual 49 cc 1.7 hp engine is assigned the number 50) and the year in which the vehicle was made, given as either a one or two letter designation and increasing by one "letter category" each full year, with an optional letter placed either before or after the year letter category and considered an amendment code. For example, the letter designation for the year 2002 for the Zuma was the letter P, so a Zuma manufactured in 2002 would have the designation YW50P. However, Yamaha made some changes to the model during its year run, so some Zumas manufactured in 2002 have the model code YW50AP to distinguish them from the YW50P model. All YW50P Zumas are identical in construction design to all other YW50P Zumas but will differ (in this particular instance, only slightly) from a YW50AP. Yamaha did not use the letter Q, and the letter for 2003 is the letter R (only one model for this year, the YW50R). For 2004, the letter S (the YW50S model). In 2008, assigned the letter X, Yamaha had two models: the YW50XL and the YW50XB. And so on. In 2011 the numbering system moved to the letter A (YW125AB for the 125 CC model and YW50AL for the 49 CC model).

The Zuma has a 14 mm Teikei carburetor with automatic choke, reed-valve induction, a fan-assisted cooling system, an autolube oil-injection system with an indicator light located on instrument panel which alerts rider when oil level gets low, and electric starting with backup kick start.

It also has five spoke-cast wheels with low-profile 120/90-10 front and 130/90-10 rear tires. The front fork has 2.6 inches (66 mm) of travel, and rear shock has 2.4 inches (61 mm) of travel. The scooter also has 155 mm hydraulic front disc brakes and rear drum brakes. (Models until 1998 had front drum brake instead of a hydraulic one.)

The dual seat contains a storage compartment adequate for a single full-face helmet. The rear cargo rack can be used for additional carrying capacity but requires the use of ropes or bungee cords to secure any load. This rack can also function as passenger grabrails. The Zuma has "Bug-eyed" dual headlights that come with one light wired to low beam and the other wired to high beam (both lamps have filaments for high and low beam functions, however, and many users install an inexpensive and simple wiring modification to make both headlamps light with both the high and low beams). The instrument panel has turn signal indicators, a high beam indicator, a low-oil indicator, a speedometer, a gas level gauge, and an odometer.

Yahama specifies that the Zuma can safely carry up to 315 lb (143 kg) of passengers and cargo. Yamaha took the Zuma off the market in the U.S. in 2006 and 2007, and then reintroduced the model in 2008–2011. In order to comply with Environmental Protection Agency regulations, the 2008 model has a restricted throttle and a catalytic converter, limiting it to a top speed of 30 mph (48 km/h), compared with around 35 mph (56 km/h) for the 2005 and earlier models. The models from 2008–2011 have a slightly higher gear ratio that helps compensate (at the expense of a little less power on take-off).

In 2011 Yamaha introduced the Zuma 125, followed in 2012 by the Zuma 50f (which replaced the 2-stroke version), both 4-stroke fuel-injected models.

Fuel Economy

The United States Environmental Protection Agency mileage estimates for the Zuma are up to 123 mpg_‑US (1.91 L/100 km; 148 mpg_‑imp), depending upon how it is ridden, maintenance, road conditions, cargo, and driver/passenger weight.

1989-2001 Zuma

Production	1989-2001
Engine	Vertical Minarelli 49 cc air-cooled, carbureted 2-stroke, electronic ignition Bore x stroke: 40.0 mm x 39.2 mm Compression ratio: 7.0:1
Top speed	40 mph (64 km/h)
Transmission	V-belt automatic
Suspension	Front: Telescopic fork Rear: Single shock
Brakes	Front: 155mm disc;drum on earlier models Rear: drum
Tires	Front: 125/90-10 Rear 125/90-10
Wheelbase	50.2 in (1,275 mm)
Dimensions	L: 68.3 in (1,735 mm) W: 24.8 in (630 mm) H: 41.5 in (1,054 mm)
Seat height	29.3 in (744 mm)
Weight	159 lb (72 kg) (dry)
Fuel capacity	1.1 US gallons (4.2 L)

Popular modifications

The Zuma '02 - '11 uses a "long case" Minarelli engine, which has a large number of aftermarket upgrades available. Many scooter hobbyists replace (among other things) the 50cc piston and cylinder with a larger-displacement 70cc model for faster acceleration and top speed; the carburetor with a larger one (17.5mm, 19mm, and 21mm are the most common sizes); the final drive gears, for a higher ratio and therefore higher top speed; and while it's not street legal in the US, the exhaust pipe.