Yamaha numbers its scooter models according to their make followed by the engine size 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 from a YW50AP. Yamaha did not use the letter Q, and the letter for 2003 is the letter R. For 2004, the letter S. 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. 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 of travel, and rear shock has of travel. The scooter also has 155 mmhydraulic front disc brakes and rear drum brakes. 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. 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 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. The models from 2008–2011 have a slightly higher gear ratio that helps compensate. In 2011 Yamaha introduced the Zuma 125, followed in 2012 by the Zuma 50f, both 4-stroke fuel-injected models.
