The Kawasaki Ninja 250R is a street motorcycle sold by the Kawasaki Motors division of Kawasaki Heavy Industries since 1983. It is Kawasaki's best-selling motorcycle, experiencing steady double-digit sales growth year after year. It is renowned for its light handling, good fuel economy, sufficient power, and relatively comfortable riding posture, making it a desirable first motorcycle for new riders, and a popular machine with experienced riders who seek a second machine, or wish to enter the sportbike category. The smallest Ninja has undergone few changes throughout its quarter-century existence, having seen only two substantial redesigns.
NomenclatureOwners and fans of the motorcycle commonly refer to it by its platform designation, EX250. This designation is followed by an alphabetical suffix indicating the generation. Before the 2008 model, the motorcycle carried different marketing names worldwide/ The 2008 (EX250-J) model is known as the Ninja 250R in all markets. In the United States, previous generations (EX-250E/F/G/H) were also marketed as members of the "Ninja" family of sportbikes, while outside the U.S. it is known as the ZZR-250, ZX-250, or as the GPX-250R. Past models (EX250-C) have carried the base designation GPZ-250. As the smallest of the Ninja motorcycles, the Ninja 250R has received the affectionate nickname "Ninjette" or "Baby Ninja".
Description and features
In many respects, including ergonomics, chassis design, engine placement within the frame, the Ninja 250R straddles standard and sport classes. Likewise, the bike's riding position falls between standard and sport. Capable of running the 1/4 mile in 14.6 seconds at 88mph,  the bike's features include bungee hooks, center stand (no longer available on the 2008 model), a tachometer, and front and rear disc brakes. 
The bike has been heavily updated for 2008 with completely redesigned fairings and 17" wheels. As of 2007, the 250R is being produced in Thailand. Kawasaki has marketed the Ninja 250R since 1986  as an entry-level  
The Ninja 250 has little direct competition within its class in the United States, partly due to it being one of the two 250 cc sport bikes sold. In Canada, Honda's 2007 introduction of the CBR125R has caused competition for Kawasaki's share in the entry-level sport bike market. The other main competitors are the other 250 cc "beginner bikes," namely the Hyosung GT250R, Honda's Rebel 250 and Nighthawk 250, the Suzuki GZ250, and the Yamaha Virago 250. With the exception of the Nighthawk, (a standard) and the Hyosung, these bikes are all cruisers.
Before the 2008 model, neither the Ninja nor these other US 250's had changed much in recent years, but outside the United States there were many advances in small-displacement, lightweight, and/or low-cost motorcycles, including several four-cylinder, sixteen-valve 250s (e.g., the Honda "Hornet" 250 or Ninja ZX-2R). That being said, the Ninja 250 enjoys a modest following among riders who appreciate its light weight and nimble handling as an amusing "track bike." The very fact that it hasn't changed much since 1988 means parts are plentiful and inexpensive, and the rider community is well established.
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