2012 NEW MOTOCROSS BIKE BUYERS GUIDE: THE 2012 YAMAHA YZ450F & YZ250F (PLUS THE PLAY BIKES ARE BACK)


Yamaha has released photos and info on the 2012 YZ250F and YZ450F, but the bikes will not be in the showrooms until September 14. The YZ125 and YZ250 two-stroke info will not be unveiled until later.

2012 YAMAHA YZ450F


There are new graphics, but the plastic remains the same on the blue 2012 YZ450F.

Since the YZ450F was totally redesigned in 2010, it only gets modest upgrades for 2012. The focus of the 2012 changes were to improve midrange power, mellow out the low-end hit and improve the suspension feel.
 
Creative design: Yamaha’s reverse cylinder design and downdraft throttle body combine to create the most advanced engine in the class.

Power profile: The 2012 powerband offers awesome low-to-mid power with improved roll-on characteristics

Tunable power: The power characteristic can be adjusted to the rider’s preference with the $279 GYTR Power Tuner.


The white YZ450F gets a swap in the position of the white and black plastic panels.

YZ450F CHASSIS AND HANDLING

Frame: Yamaha’s unique double “S” bend bilateral beam frame helps produce the ultimate centralization of mass

Rigidity: Chassis rigidity is very balanced and forgiving in rough sections. The light handling makes it one of the best in class when it comes to carving tight inside lines through corners, yet it is still very stable and neutral.

2012 YZ450F SUSPENSION

Suspension: Outstanding suspension comfort and bump absorption due to the Kayaba SSS front forks and large capacity piggyback shock. Yamaha offers suspension settings that suit a wide range of riders thanks to a rigorous testing program.

Fork: The 48mm KYB Speed Sensitive System (SSS) Front forks have been revalved to increase low-to-mid compression damping.

Shock: The KYB 50mm rear shock has revised rebound damping, a new rebound adjuster oil passage and improved valving with less low-speed rebound and more high-speed compression.


Last year the American bikes had silver rims, while the rest of the world got black rims?for 2012 the USA gets the black rims also.

Rims: The Excel rims have been anodized black (they were silver in 2011).


The 2012 muffler has a 3mm smaller diameter core and is 42mm longer than in 2011.

2012 YZ450F COMPONENTS
 
Handlebars: The YZ450F and YZ250F come with Pro Taper handlebars mounted to four-position capable top triple clamp/bar mounts

Footpegs: Ultra-Wide footpegs.

Sprockets: Sunstar sprockets and Gold D.I.D. Chain

Brakes: Braking rotors. 

Tires: Dunlop Geomax MX51 Tires.

Ignition: Fuel map and ignition timing optimized.

Muffler: The 2012 muffler is 42mm longer and has a 3mm smaller core diameter. It is both AMA 94 dB and FIM Two-Meter-Max legal.

Shift fork: The locating pin on the shift fork has been changed to a circlip to increase shift bar rigidity for more precise shifting from second to third.

2012 YAMAHA YZ250F


The 2012 Yamaha YZ250F may look unchanged, but Yamaha moved the power up in the powerband, stiffened the suspension and worked on the frame.

The Yamaha YZ250F is the most reliable engine in the 250 class and (in the hands of Yamaha’s racing teams and riders like Ryan Sipes and Kyle Cunningham) it has proved to be capable of being hopped-up to be among the fastest bikes on the National/Supercross circuit.


If you are paying the bills, the proven YZ250F engine is a great buy. It is the most reliable 250cc four-stroke engine made.

If you were expecting fuel injection on the 2012 Yamaha YZ250F, you should not be disappointed to learn that Yamaha stuck with the venerable Keihin FCR carburetor. This is not a negative, since a well-jetted carb can produce a broader powerband and more horsepower than a EFI 250?especially when mated to a series of thoughtful upgrades.


Yamaha changed the mapping and upped the Keihin FCR carb from 37mm to 39mm in search of more top-end power.

Carb: For 2012 the YZ250F gets a 2mm large carb bore from 37mm to 39mm (for more top-end power?especially from 8000 rpm to 12,000 rpm). Additionally, Yamaha reduced the reciprocating mass of the piston and the balance of the crankshaft (which also reduces vibration at the bars, pegs and saddle). There is also a new air filter cage that flows more air to go along with the revised engine mapping (for more mid and top) and a muffler with an 8mm smaller core diameter (the 2012 muffler will meet AMA and FIM sound standards).

Piston: The piston is 8.7 percent lighter than it was last year (and the piston pin is not offset as it was in 2011). Plus, it gets piston rings with reduced friction and a lighter piston pin and circlips.

Crank: The crankshaft balance and counter-balancer have been revised for smoother performance. Additionally, the connecting rod and big-end bearing get a new heat-treating process for more strength and improved durability.


The KYB rear shock has not only been revalved, but the shock shaft has been downsized from 18mm to 16mm.

2012 YZ250F SUSPENSION

Forks: The Kayaba Speed Sensitive System (SSS) front forks have been revalved to ride higher in their stroke (to lessen diving) and the spring rate has been increased from 0.45 kg/mm to 0.46 kg/mm. The outer fork tube has been reshaped to provide a better flex characteristic.

Fork offset: Fork offset has been changed from 25mm to 22mm and the steering stem has been increased in length.

Shock: The 46mm Kayaba SSS rear shocks has revised damping and a 16mm shock shaft (it was 18mm in 2011).

Swingarm: The axle blocks at the back of the swingarm have been beefed up to increase the rigidity of the rear axle.

Gearing: The 2012 Yamaha YZ250F gets a 50-tooth rear sprocket?instead of last year’s 49.


Even the naked eye can see how much larger the frame rails are at the swingarm pivot.

2012 YZ250F CHASSIS AND HANDLING

The 2012 Yamaha YZ250F gets a new frame. Here is a list of the chassis changes.

    (1) The new frame is made up of 20 different cast, forged, machined and extruded pieces.

    (2) The frame rails have been changed from a double-box extrusion to a triple box extrusion for more rigidity.


The YZ250F axle blocks have been beefed up and the gearing has been lowered for more drive out of corners.

    (3) The sections of the frame that houses the swingarm pivot have been increased in width and thickness to support the rear suspension on all axis for more precise handling.

    (4) The motor mounts have been changed in thickness and shape.


Both the YZ450F and YZ250F will get the gold DID chain.

2012 YAMAHA PW50

2012 YAMAHA TT-R110

2012 YAMAHA TT-R125L

2012 YAMAHA TT-R230

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