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2008 Suzuki RM-Z450 Intro

Yesterday was the day that every magazine editor was impatiently waiting for – the arrival of the 2008 Suzuki RM-Z450. To say that Suzuki’s flagship motocross bike is all new for 2008 would be a severe understatement. There are very few parts that the 2007 and ?08 model share, such as the air filter and oil filter. Beyond that, the fuel-injected RM-Z450 was built from the ground up.   The MXA wrecking crew met with Suzuki personnel at Perris Raceway in southern California to sling a leg over t…

Applied Racing’s New CRF Triple Clamps

Press Release- ?Applied Racing is excited to announce a brand new triple clamp design for 2008 CRF 250R/450R/450X.   As usual, much time and effort was made by engineers and testers at Applied to make this our best triple clamp yet. The most noticeable difference is the weight (or lack of)! Compared to the stock upper and lower clamp set, our set is still almost 5/8 of a pound lighter!  And, don?t worry.  You can still keep your Honda dampener.  The set is completely CNC machine…

Two New 2008 Bikes From Yamaha (WR and WRX)

 Yamaha is introducing the all new WR250R and WR250X.The WR250R is a dual purpose machine that blends a mixture of love for both the street and the dirt. The WR250X with it’s 17″ wheels is nothing short of SuperMoto inspired. Both bikes feature an all new DOHC four valve 250cc four-stroke engine, with a six speed transmission and FUEL INJECTION, a first for this class.   Directly descended from our YZ motocrossers and WR off-road machines?even the original Yamaha YA-1 of 1955?the all-new WR250…

2008 Honda CRF250R Unveiled

  First Look: 2008 CRF 250R ? New piston with 13.1:1 compression ratio ? New cylinder head porting for improved power ? New lighter-weight valve train components raise rev limit to 13,500 rpm ? New lighter counterbalancer shaft and drive gears. ? New exhaust system for more power ? New camshaft timing for added power ? Revised carburetor jetting gives smooth power delivery under all riding conditions ? Engine torque now reaches maximum at 8500 rpm. ? New…

2008 Honda CRF450R Unveiled

  First Look: 2008 Honda CRF 450R Although the MXA wrecking crew have been racing their 2008 Honda MX bikes for a few weeks already, it wasn’t until today that we could officially release the information. While we’ve already gone over the bikes with a fine toothed comb, new to us was the limited release black version (for both the 450 and 250).  ? New tapered exhaust head pipe improves low-end and midrange power. ? New lighter counterbalancer shaft and drive gears. ? New works-t…

First Look: 2008 Suzuki RM-Z450

  New Features Hot start lever is relocated to the right hand side of the handlebar for easy operation while holding the clutch. Race inspired wave-rotors provide better cooling performance and increased mud deflection in muddy conditions. Gripper seat has been improved this year by adding projected cross-shaped patterns on the top surface to provide additional grip. New Engine Electronic Fuel Injection offers better roll on power and improved low-to-mid range power. KEIHIN throttle body specifical…

2008 KTM Intro: Are You Ready For Electric Start Two-Strokes?

When KTM rider Cyril Despres recently won his third victory in the Red Bull Romaniacs Hard Enduro he became the first rider to win on the new 300 EXC-E (which is KTM’s new electric-start 300cc two-stroke). According to Despres, “As riders, we are always concerned about the bikes having any extra weight and I was a bit unsure before the race about the addition of the battery and the electronic starter for that reason. But I have to say it was very helpful in many situations and it is definitely an advant…

2008 KTM’S

2008 KTM 450SXF What’s new on the 2008 KTM 450SXF: (1) The crankshaft weight has been reduced, but the inertia has been increased (by moving the weight farther out on the flywheels). (2) KTM’s dual counterbalancers have been reduced in weight for snappier throttle response. (3) The clutch shaft, clutch hub and clutch basket have been modified to increase oil flow for better feel and less engine heat. (4) A new exhaust cam, with new timing has been added to improved ow-end power. (5) The muffler is quiet…

First Look: 2008 Kawasaki KX250F

 Features and Benefits Engine – 249cc, liquid-cooled, four-stroke, four-valve, DOHC engine delivers hard-hitting power from mid- to high-rpm – Features improvements in rigidity and reliability – Wide powerband for excellent low-rpm torque and blistering over-rev Top End – Polished intake ports for an extremely-smooth surface that improves intake flow at every rpm – Ultra-light thin-stem titanium valves feature thick skirts and extended guides for maximum durability – New head gasket offers better se…

First Look: 2008 Kawasaki KX450F

 Features and Benefits Engine – 449cc liquid-cooled, DOHC, four-stroke single with lightweight, oxidized membrane treated titanium valves – High-acceleration cams help the engine rev quickly – Revised piston-cooling oil jet – Fifth bolt added to oil pump cover for improved sealing – Dual overhead, lightweight camshafts feature a soft-nitride surface treatment for long wear and high-rpm reliability – Special coating on the intake ports improve intake efficiency at all rpm – Titanium 36mm intake and 3…

INTRODUCING THE 2008 HONDA CRF150R

  Engine/Drivetrain High-Performance Unicam? cylinder head design (see Technology Section) Lightweight, compact, internal auto decompression and handlebar-mounted hot-start system provide easy starting, hot or cold. Compact, lightweight engine assembly weighs only 43.6 pounds. Crankshaft is made of high-strength, low-carbon steel with carburized main journals for maximum durability at sustained high-rpm operation. Forged 11.7:1-compression slipper piston and rings are lighter than a conventional des…

DRD: New CRF Radiator Lowering Kits

Norco , CA. (May 29, 2007)  Dubach Racing Development (DRD), is proud to announce immediate availability for the new CRF Radiator Lowering Kits.   DRD delivers a factory-level modification that improves handling, is simple to install and retails for $49.95   Radiator Lowering Kits help to lower the center of gravity improving the CRF’s handling character, most notably, entering and exciting corners when the bike is laid over.   Best of all, this modification is easy enough for any ri…

MXA’S 2007 KAWASAKI KX250 RACE TEST

It is entirely possible that the 2007 Kawasaki KX250 is living on borrowed time. Last year, with little or no warning, Kawasaki dropped the KX125 from its lineup. The fact that the KX250 survived into 2007, albeit unchanged, is a testament to the hard-core loyalty of two-stroke fans. Kawasaki doesn’t want to abandon riders who are looking for a low-cost, easy-to-maintain, lightweight and snappy race machine. That list of attributes can only be applied to a two-stroke. By comparison, four-strokes are hig…

MXA BIKE TEST: 2007 YZ250

The truth about 250cc two-strokes is that they are wonderful pieces of racing machinerytechnically advanced, lightweight, blazing fast, cheap to maintain, and capable of being worked on with backyard tools. All of that is undeniableas is the fact that the modern motocross two-stroke can be found in the encyclopedia right next to the now-extinct dodo bird. Of the four Japanese manufacturers, Yamaha is in the catbird seat when it comes to two-strokes. They own the two-stroke market. When they introduced t…

2007 KAWASAKI KX250F INFORMATION

(press release) Kawasaki’s all-new four-stroke KX?250F rose to the top to become one of last years best motocross bikes. For 2007, Kawasaki improves the championship winning KX250F with a host of engine and chassis modifications designed to extend its performance advantage. Side view of the 2007 KX250FSide view of the 2007 KX250FSide view of the 2007 KX250FSide view of the 2007 KX250FSide view of the 2007 KX250F Side view of the 2007 KX250F Refinements to Kawasaki’s highly acclaimed KX250F make it an eve…

WE RIDE CHAD REED’S WORKS YAMAHA YZ450F

GETTING A CHANCE TO TEST RIDE A WORKS BIKE, IN THE MIDDLE OF THE AMA RACING SEASON, WOULD BE LIKE  FERRARI LETTING YOU TAKE MICHAEL SCHUMACHER’S FERRARI DOWN TO THE STORE FOR A QUART OF MILK ON THE EVE OF THE GRAND PRIX OF MONACO. Getting a chance to test ride a works bike, in the middle of the AMA racing season, would be like Ferrari letting you take Michael Schumacher’s Ferrari down to the store for a quart of milk on the eve of the Grand Prix of Monaco. Factory teams are protective of their mach…

WE RIDE MAXPOWER/RPM’S BIG-BORE KX315

    WITH TODAY’S METALLURGICAL CONFIGURATIONS, IT IS POSSIBLE TO MAKE AN ENGINE PRODUCE MORE POWER, ACCELERATION, SPEED AND SENSATIONS THAN THE HUMAN MIND CAN PROCESS OR HUMAN BODY MANAGE.             Formula 1 race car designers, from as far back as Colin Chapman, have understood that there is a delicate balance between weight and power. In truth, the never-ending pursuit of power has pretty much ended, and if it weren’t for computer mana…

MXA PRODUCT TEST: PRO CIRCUIT KX450F LINKAGE AND REVALVE

WHAT IS IT? An aftermarket shock linkage and shock revalve for the 2006 Kawasaki KX450F that alters the rising rate, lowers the seat height and mitigates bottoming.
WHAT’S IT COST? $184.95 (linkage), $149.95 (shock revalve) and $7.95 (shock oil)(951) 738-8050. www.procircuit.com     WHAT’S IT DO? Every MXA test rider has concerns about the rear suspension of the 2006 KX450F. In stock trim, it wallows (sways under acceleration), bottoms (so hard that it can break the rear fe…

2007 YAMAHAS

YZ450F New for 2007: Replacing the upper cast triple clamp with a light and strong forging, slightly reducing steering head rigidity, and the use of lighter outer fork tubes; lighter wheel rims and light wave-type brake rotors add up to super-accurate, super-responsive steering. Increasing the length of the rear shock by 1.5mm further sharpens handling. Replacing steel damping adjusters with aluminum ones removes even more weight from the four-way adjustable, titanium-sprung rear suspension unit. A more…

NEW BIKES: 2007 KAWASAKIS

  KX250F Kawasaki’s all-new four-stroke KX250F rose to the top to become one of last years best motocross bikes. For 2007, Kawasaki improves the championship-winning KX250F with a host of engine and chassis modifications designed to extend its performance advantage. Refinements to Kawasaki’s highly acclaimed KX250F make it an even more potent track weapon. The newest KX250F keeps the outstanding top-end power from last year’s bike, but adds a stronger pull from the bottom of its rev range. The upgr…

2007 SUZUKIS

RM 125  2007 RM125 Get ready for a shot of mid-range designed to help you blast past the competition. The RM125 has a wider powerband and more controllable power delivery than ever. Couple that smooth, strong power and refined suspension systems front and rear, and you’ve got the hottest one-two-five on the track. So get in on Suzuki’s winning tradition, with the 2007 RM125. RM-Z 250 2007 RM-Z250 The 2007 RM-Z250 is all new from the ground up and it is 100% Suzuki. The RM-Z250 features a compact, l…

WE RIDE SEAN COLLIER’S STAR RACING YAMAHA YZ250F

  IT’S NO SECRET THAT EVERY RACE TEAM LIKES TO THINK OF THEMSELVES AS THE CENTER OF THE UNIVERSE.  IT’S HUMAN NATURE TO THINK THAT EVERY MOTOCROSS FAN KNOWS WHO THEY ARE. As he’s a neighbor of Motocross Action’s managing editor Tim Olson, we’d love to say Sean Collier volunteered to let the MXA wrecking crew take his 2006 Star Racing YZ250F and thrash on it. Truth is, Sean was busy at the Yamaha Supercross test track in Corona, California, and wouldn’t be able to help us in our quest to try ou…

WE RIDE PRO-CIRCUIT’S RC REPLICA RM-Z450

    THANKS TO THE AMA PRODUCTION RULE, AS FEEBLY ENFORCED AS IT IS, MOST FACTORY RACE BIKES ARE FINELY TUNED VERSIONS OF SHOWROOM STOCKERS. What’s the difference between a works bike and a stock bike? Cubic dollars. Big bucks. Massive infusions of loot. Moolah. Filthy lucre. Greenbacks. What does all that cash buy? You probably think that it buys exotic one-off parts. Not true. Most of the trick parts on a modern works bike are obtainable on the open market. Thanks to the AMA production r…

WE RIDE PIONEER’S BIG-BORE SUZUKI RM-Z475

  NAMED AFTER THE EMBARRASSINGLY SHALLOW MTV SHOW, WHERE CELEBRITIES SHOW OFF THEIR  HOMES, SHOES, CARS AND SPAS, THE “CRIBS EFFECT” HAS SPREAD THROUGHOUT EVERY SOCIAL STRATA OF AMERICAN SOCIETY. Pssst! Wanna know a secret? Four-stroke buyers are bucks-up. They are better off financially than any group of motocross racers in the 35-year history of the sport. Suddenly, it appears as though everybody in America is rich?ostentatiously so. Modern racers are more than willing to spend beaucoup mone…

WE RIDE MB1/TOKYO MODS HONDA CRF450

  Einstein’s theory: Tokyo Mods’ engine formula is simple. Make the most power and make it right now. AS PART OF THE MXA FAITHFUL, YOU NO DOUBT REMEMBER THAT WE TESTED BOTH A STAND-ALONE MB1/TOKYO MODS HONDA CRF250 AND A CRF450 IN OUR INFAMOUS BLIND-TASTE-TEST PEPSI CHALLENGE. This isn’t the MXA wrecking crew’s first rodeo with the MB1 and Tokyo Mods boys. As part of the MXA faithful, you no doubt remember that we tested both a stand-alone MB1/Tokyo Mods Honda CRF250 and a CRF450 in our infamous bl…

2007 HONDA CRF450R

New for 2007 New larger 41mm Keihin FCR carburetor. New smaller exhaust valve for improved flow and smoother power delivery. Engine decompression system is lighter and more compact. New link-type front brake master cylinder improves front braking power by 15 percent. New Dunlop 742FA front tire for improved turning feel and traction. New subframe allows the muffler to be mounted farther forward for better mass-centralization. Lighter rear chain guide. Stronger clutch basket and clutch center for improve…

2007 HONDA CRF250R

New for 2007 New camshaft and cylinder-head porting improve power output above 8000 rpm. New intake valve springs match new camshaft. New crankcase venting for improved engine power. New exhaust header works in conjunction with new camshaft. New carburetor features new-styled accelerator pump and linkage for improved throttle response. New clutch basket features increased thickness for additional strength. New ignition map with 13,370-rpm rev limit. New link-type front brake master cylinder improves fro…

WE RIDE DR. D’S HONDA CRF450

Bullet train: MXA’s melding of Suzuki, Yamaha and Kawasaki specialists produced a Honda CRF450 that is untouchable. You better be ready before you pull the trigger.   HISTORICALLY, FACTORY RIDERS MAKE BAD TEST RIDERS FOR ANYONE BUT THEMSELVES AND, UNFORTUNATELY FOR THE SALES DEPARTMENT, THEY DON’T PAY FOR THEIR BIKES. Test riders with the knowledge and gumption to tell the factory test engineers the truth are hard to come by. Don’t think that you can find them on the race teams?no way. Fast motorcy…

2006 YAMAHA YZ250F TEST

  As much as a giant, monolithic, multinational corporation can be, Yamaha is a rebel. As a rule of thumb, Yamaha always takes the road less traveled. Need proof? How about the first single-shock motocross bike (Monoshock)? First Brake Activated Suspension System (BASS)? First power valve-equipped exhaust port (YPVS)? First aluminum-framed works bike (YZM500)? Or, the granddaddy of all firsts, the first modern-era four-stroke motocross bikes?   While the rest of the manufacturers were busy per…

MXA PRODUCT TEST: YOSHIMURA RS3 CRF250 EXHAUST

  WHAT IS IT? Yoshimura’s take on the Honda twin-piper.   WHAT’S IT COST? $1175.00 (carbon fiber), $1075.00 (titanium), $750.00 (stainless steel)(909) 628-4722. http://www.yoshimura-rd.com   WHAT’S IT DO? Honda’s new twin-pipe exhaust has been a mixed bag for the consumer. Everyone thinks the design looks really cool, but very few feel, hear or see any actual difference in performance. Most devastating for consumer confidence is that buyers are scared to death about what it will cost to r…