YZ250

Infobox Motorcycle
name = YZ250X


aka =
manufacturer = Yamaha
parent_company =
production = 1974-
predecessor =
successor = YZ450
class = Motocross
engine = 250 cc single-cylinder, water-cooled, two-stroke, case reed
power = 47 hp [ [http://www.dirtrider.com/tests/164_0402_jday/photo_10.html 164 0402 Jday 45 Z Photo ] ]
torque = 29 ft·lbf [ibid]
transmission = 5-speed
suspension = Monoshock, 12.8 inches travel
brakes = double disc
tires = Front: 80/100-21-51M ; Rear: 110/90-19-62M
rake_trail =
wheelbase = 57.8 inches
length= 85 inches
width= 32.5 inches
height= 51.2 inches
seat_height = 39.1 inches
dry_weight = convert|212|lb|abbr=on
wet_weight =
fuel_capacity = 2.1 US gallons
related = Yamaha YZ450F
similar = Kawasaki KX450F, Honda CRF450, Suzuki RMF450The YZ250 is a legendary 2-stroke motocross race bike made by Yamaha. It was launched in the 1970s, and has been regularly updated since. It is slowly being phased out and replaced by its four stroke rival, the YZ450F.

Engine

The YZ250 has a 249 cc liquid-cooled two stroke reed valved engine with a YPVS exhaust valve for a wider spread of power. The engine produces convert|47|hp and convert|29|ft.lbf|N.m of torque, with a 9,000 rpm redline. [http://img.photobucket.com/albums/v665/mattskn/dyno001.jpg]

Chassis

Since its introduction in 1974, the YZ250 has had a single backbone steel frame. For the 2005 model year, however, the YZ250 has a new perimeter frame made entirely from aluminum, which brought the dry weight down to 212 pounds. [http://www.yamaha-motor.com/sport/products/modelspecs/30/0/specs.aspx 2008 Yamaha YZ250 Specifications, specs, spec ] ] The bike has a Swingarm rear suspension system with more than a foot of travel, as well as telescopic inverted forks with convert|11.8|in|mm of travel. Front and rear hydraulic disc brakes round out the YZ.

Championships

The YZ250 holds many championships:
*5 AMA National Motocross Titles [http://www.motocrossactionmag.com/me2/dirsect.asp?sid=9945527E1D6A4953ACE23BB700C838FF&nm=EVERY+CHAMP EVERY CHAMP | Motocross Action ] ]
*9 AMA National Supercross Titles
*Most recently, Chad Reed rode the YZ250 to an AMA National Supercross title in 2004. [ [http://www.amaproracing.com/prorace/raceres/sx/totpoints.asp?cls=s2&snct=p6080&year=2004 AMAMotocross.com - 2004 AMA THQ Supercross Series results ] ]

ee also

*YZ125
*YZ250F

References