More power, great new suspension. What else do you need to know?
For 2005, chassis and engine refinement continue to leave the
competition farther behind.
The all-new 48mm fork finds its way onto the front of YZ250F's
sharp-handling frame, and the trick new shock out back controls a
more rigidly mounted, lighter swingarm. The result is better feel
and feedback, consistent damping, and more comfort, all of which
makes those long motos feel shorter.
More power unravels laps quicker too, especially since the
redesigned engine delivers it super smooth from the instant you open
the throttle.
New intake ports
New combustion chamber
New piston
Revised ignition mapping
... have all been engineered to produce smoother power and more
of it, followed by a linear transition into the YZ250F's 13,500-rpm
top end.
Add YZ handling and you've got the winner of the 2004 model, 250
four-stroke shootouts in Dirt Bike, Motocross Action and Cycle News.
This year, the horses are even more ready, willing and able.
Saddle up. Ride hard.
Manufacturer's Suggested Retail Price...$5,699*
Click on images to enlarge
Features
New for 2005
Redesigned
combustion chamber, piston, intake ports, carburetor jetting and airbox for
improved combustion efficiency and power.
Redesigned CDI unit for optimal ignition timing.
All-new fork with TCV (transfer control valve) for stable
damping, improved mid- to full-stroke performance and better rider feedback.
New, aluminum Renthal handlebar is 90 grams lighter and more
durable.
Revised
triple clamps for even better handling.
Shorter,
re-routed front brake hose for increased brake feel and easier bleeding.
Lighter, stronger swingarm with stronger new linkage for
better performance and durability.
Rear shock has a new, full-rebound oil lock circuit for a
smoother ride.
New-design rear sprocket and chain guide reduces wear, chain
wobble, and noise for more efficient power transfer.
Rear brake bracket is 35 grams lighter, and designed for
easier rear wheel installation.
New front fork protectors are larger for better coverage.
Engine:
Liquid-cooled, 249cc, five-valve, DOHC, four-stroke is the
world’s most powerful quarter-liter four-stroke motocrosser. The
stratospherically high 13,500-rpm redline means incomparable,
competition-crushing pulling power.
Titanium valves and load-reduced springs decrease weight by
more than 40 percent and reduce reciprocating mass for
faster-revving, harder-hitting power delivery across the rev
range.
Light, dished forged piston reduces reciprocal mass and
friction for faster revving and greater durability.
Lightweight titanium header pipe (with titanium heat shield)
flows to a repackable aluminum silencer for maximum power.
Cylinder body and crankcase feature a large cut-away section
to reduce pumping loss and increase mid-range performance.
Primary kickstarting (with automatic decompression and
convenient handlebar-mounted hot start lever) ensures easy
restarts.
Slick, 5-speed transmission with heavy-duty, multi-plate
clutch features an involute spline set-up, ensuring smoother
shifting and instant hook-up under power.
37mm Keihin FCR flat-slide carburetor with throttle position
sensor (TPS) ensures precise fuel/air mixing and lightning-quick
throttle response.
Digital CD ignition system delivers precise spark for optimal
timing for faster, stronger response during hard acceleration.
Dry sump lubrication system uses frame as oil tank, helping to
create a more compact engine and chassis for superb handling
performance.
Magnesium cylinder head cover helps shave weight.
Trick, works-style clutch lever features race-spec barrel
adjuster for on-the-fly adjustability.
Chassis/Suspension:
Removable aluminum rear subframe constructed of square-section
pipe for light weight and easy maintenance.
More weight reduction via two-piece (part aluminum, part
plastic) engine protector plates and thinner-walled engine guard
construction.
Super-strong frame is lightweight and laterally rigid for
minimal flex and razor-sharp handling.
Rear suspension system features fully adjustable Kayaba shock
with 12.4 inches of travel, separate adjusters for high- and
low-speed compression damping, and new rebound circuitry for an
improved ride.
Lightweight front and rear calipers with aluminum pistons and
anti-bubble front master cylinder, 250mm fully floating front and
245mm rear discs, deliver strong stopping power with progressive
feel.
Lightweight 21-inch front and 19-inch rear rims provide
exceptional durability and reduced unsprung weight for optimal
suspension performance.
Premium Dunlop 739 knobbies offer unbeatable, competition-spec
traction and wear.
