Dirt Class of 2010
DIRT CLASS OF 2010
The carburetor's last bastion of strength—the motocross world—continues to crumble in the face of fuel-injection's forward march. Two years after Suzuki got the motocross EFI bandwagon rolling with its RM-Z450 in 2008 (Honda and Kawasaki hopped on board with 450s last year), the Lites class has come to life with recently announced 2010 fuel-injected models.
Leading the charge is Suzuki with its RM-Z250. This time, however, Suzuki won't go it alone, as Honda also is introducing its own EFI-equipped CRF25OR. Yamaha has decided to play the conservative role (as it has in the 450 class), heavily revising its YZ25OF yet sticking with a tried-and-true car buretor.
On the off-road front, Suzuki, without much fanfare, has also an nounced the release of a brand-new competition-ready enduro called the RMX45OZ, based on the RM-Z450. As we went to press, no pricing was available from Suzuki or Yamaha on their models. Blame ample 2009 inven tory and fluctuating exchange rates. -Blake Conner
Suzuki RM-Z250
In addition to a batteryless injection system with a 43mm throttle body, the engine receives updated cam timing, a stronger connecting rod and crankshaft, and a higher, 13,500-rpm rev limit. Updated Showa suspension and new graphics are also spec'd.
Honda CRF250R
A completely redesigned, more compact Unicam engine features Programmed Fuel-Injection with a 50mm throttle body. New twin-spar aluminum frame, revised Showa suspension, a single-muffler exhaust and redesigned bodywork highlight other changes. MSRP is $7199.
Yamaha YZ250F
Changes to the YZ engine aimed at improving low-end and midrange response include revised cam timing, a different carburetor, reshaped exhaust ports and an updated exhaust. A new frame with revised geometry and suspension settings, and redesigned bodywork are the other major updates.
Suzuki RMX450Z
Based on the RM-Z, the RMX shares the same Keihin fuel-injection system that contributes to the offroader's "green-sticker" eligibility in California. Electric start, a wide-ratio five-speed transmission, a headlight and other off-road necessities make the RMX trail-ready.
