2009 Honda CRF450R Preview

Chassis

2009 Honda CRF450R

Honda’s twin-spar aluminum frame with forged aluminum steering head has long proven its worth, and because the new, smaller and lighter engine allowed a full redesign of the frame, the 2009 CRF450R now enjoys the benefits of an all-new iteration that is 14 ounces lighter than the previous version and also significantly narrower. The height of the main frame spars was reduced from 70mm to 66mm and they were also narrowed, 26mm compared to 27mm. Stronger down tubes improve front-end feel, and steering response and overall handling have been improved by moving the steering head pipe back 10mm and giving the frame a slightly steeper caster angle. As a result, the front wheel is now positioned 15mm farther back than before, significantly closer to the crankshaft, which further enhances handling. These changes to steering geometry result in steering action that is lighter, yet at the same time the new engine positioning means there’s more weight on the front wheel for more traction, so the CRF450R turns better, esp
ecially under hard acceleration.

In back, the swingarm is 18mm longer than last year’s for improved traction and the swingarm cross-member wall thickness was reduced from 3.75mm to 3.0mm to save weight. Overall changes to the frame, steering head and swingarm permit a reduction in triple clamp offset from 22mm to 20mm. New forged swingarm pivot plates increase rigidity for improved handling, and the lower engine frame rails are widened for added strength but also beveled to provide added cornering clearance—a smart touch riders will appreciate when deep in a cornering rut. Also, the removable rear subframe features an unusual, almost oval tube shape; flatter on the sides of the tubes to further narrow the bike’s profile for superior riding ergonomics, and also shaped to eliminate brackets and cross-members and facilitate improved air-filter access.

Introduced in 2008 as a means to sharpen handling, lighten steering traits and enhance straight-line performance, the Honda Progressive Steering Damper (HPSD), which features a compact damper attached to the lower triple clamp, is still employed. Thanks to the steadying influence of HPSD, more aggressive steering geometry could be engineered into the CRF450R, which is reflected by the 20mm of offset in the 2009 triple clamps, for improved cornering agility without giving up anything in high-speed handling. In addition, this year’s damper has been revalved to better match the steering traits of the 2009 setup, and it also yields a more linear damping effect. In keeping with last year’s debut, perhaps the most impressive attribute of HPSD is that it works so seamlessly with the chassis as a whole to build rider confidence; you don’t even notice it’s there.

During the process of building the all-new frame into a complete rolling chassis, all options for attendant suspension components were considered. After much testing, the new 2009 CRF450R was given a new, sophisticated Honda-specific Kayaba inverted Air-Oil-Separated (AOS) fork with 48mm-diameter fork legs (up from 47mm last year) that features fully adjustable compression and rebound damping and spring settings developed specifically for the CRF450R. And Honda’s proven Pro-Link® Rear Suspension also now incorporates a fully adjustable Kayaba shock made specifically for the CRF450R that features an integrated reservoir plus all-new damping and spring settings. The large 50mm-diameter rear shock piston contributes to consistent performance under the most demanding riding conditions. As a result, both ends feel calmer while riding, demonstrating exceptional bump compliance and suspension plushness. This allows the CRF450R to follow bumps better and accelerate harder over choppy terrain.

Thanks to the all-new chassis and engine, the new CRF450R is now 3.0 pounds lighter than last year’s 450R in actual weight, which makes it a class standout in 2009.Weighing 234.8 pounds gassed and ready to go, the CRF450R is now encroaching on the 250F-class neighborhood. And better yet, the myriad chassis changes make the machine markedly slimmer than ever before, so it feels even lighter than it is.

Astride the bike, the rider can immediately sense a much more open riding position; it’s so easy to move around, the CRF450R creates a distinctly more modern feeling. This agile nature becomes especially noticeable when leaning the bike over, cornering and jumping, where it feels significantly more maneuverable. Also, thanks to the new chassis geometry the CRF450R’s steering action feels distinctly lighter, yet there’s more weight on the front wheel for more traction, so it also turns better than ever before. Bottom line: The 2008 CRF450R already had the lightest weight and best handling in class, but now in 2009 it has leapfrogged far ahead of everyone else. This is, by a good margin, the best-handling CRF450R Honda has ever made.

Other chassis highlights include a front wheel with a new, stiffer axle collar. A large-diameter front axle and wide wheel-bearing span provide excellent rigidity. A new rear axle features a diameter of25mm and large-diameter bearings provide additional rigidity. Axle wall thickness has been reduced from2.5mm to 2.2mm to save unsprung weight (38 grams), and the rear axle collar is also a new, stronger item.

The HRC works-style rear brake system integrates the rear master cylinder and fluid reservoir, eliminating a separate reservoir and hose. The link-type front brake master cylinder and a lightweight brake rotor provide strong braking; the re-shaped works-style 240mm front brake rotor is also 1.3 ounces lighter than before, and the front disc guard is now smaller, lighter and vented. In back, the 240mm rear brake rotor features a works-style pattern and is 1.0 ounce lighter, while a new plastic disc guard saves an additional 4 grams. Both front and rear wheels feature HRC works-type lightweight aluminum spoke nipples.

2009 Honda CRF450R

In the attention-to-details department, thoughtful touches abound. A new gray color coats the lightweight magnesium head cover, clutch cover and left sidecover; note that the clutch cover has been dished inward for improved foot placement. On the left side resides a new low-profile oil dipstick. A newly designed high-capacity airbox is lighter in weight and improves filter access, and the redesigned sidecover that dovetails into the side panel of the airbox is narrower and improves airflow into the airbox.

Redesigned radiator shrouds are narrowed to aid rider movement and the kickstarter arm is reshaped to reduce weight. A new seat base reduces overall height and width while maintaining the same amount of foam thickness. New handgrips with a softer compound, new surface pattern and safety-wire grooves are also3mmlonger than before, which permitted the use of shorter cables and brake hose to reduce weight—unsurpassed attention to detail even in areas that might otherwise go unnoticed. The front and rear fenders are redesigned for greater rigidity and the rear fender shape helps prevent mud and debris from gathering on the muffler.

Removable engine mounts allow easier engine removal, and the narrower engine allows elimination of the right-side engine guard to save weight. A new fuel tank tether cable eliminates the need to disconnect the fuel line when accessing the top of the engine—a handy aid to routine maintenance. The plastic fuel tank has been strengthened to ensure proper sealing for the lightweight plastic fuel pump, which resides within the tank. Rider ergonomics are optimized by adapting the handlebar, seat and footpeg height to give the rider a distinctly narrowed perch for improved comfort and handling feel, and the lightweight aluminum brake pedal and shift lever are designed to complement the CRF450R’s new ergonomics. As one final note, the fuel cap is shorter than before to allow the rider to easily move farther forward on the tank.

For many, the value of the 2009 CRF450R will be shown on the stopwatch and with the acquisition of trophies. However, there’s also a deeper story here, one that emerges with the sum total of countless changes—large and small—that add up to a true next-generation machine, a significant milestone in motocross design. The 2009 CRF450R has vaulted so far ahead that it redefines expectations in the premium class of motocrossers.

Price

Although it clearly occupies the position of class leader, the Honda CRF450R isn’t financially demanding at all compared to the rest of the bikes in its class. Having an MSRP of $7,599, it simply requires $50 more than Kawasaki’s KX450F, $100 more that Suzuki’s RM-Z450 and $200 more than Yamaha’s YZ450F $7,399. Now really, can you ask for more?

Conclusion

In the all-new and lighter 2009 CRF450R, a brand-new engine with electronic fuel injection, developed concurrently with an entirely new rolling chassis, work together to deliver 450- class-leading power along with CRF250R-style handling. It’s an unprecedented blend of power, suspension and handling that together bring a genuine revolution to the premier motocross class.

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