We get our first taste of the all-new Honda CRF450R

It’s hard to believe it’s been 15 years since the first Honda CRF450R hit showroom floors, nestled among numerous two-strokes MX bikes. At the time, four-strokes were the redheaded stepchild, not the norm. The early 2000’s saw the beginning of major change in the world of motocross and that change has continued to shape motocross as we know it. Many thought the four-stroke was a fad, a niche market that only some would embrace. Two-stroke motocross bikes? In 2016 that is the oddity.

All-New Means All-New

All-new is an overused and worn out term, but there really is no better way to describe the 2017 Honda CRF450R—it is 99% new, enough to easily and freely call it that tired and often times inaccurately used term. At the center of this truly all-new CRF450R is the engine, which is now more compact and lighter while retaining the basic previous design. An all-new Unicam design is more compact and uses a finger rocker arm on the intake valves. All valves now use an oval-coil cross-section valve reducing the overall engine height. Narrower valve angles help to improve combustion, while the intake valve size increased 2mm to 38mm. Honda claims the head changes increase intake efficiency by 19% and exhaust flow by 10%. With a revised squish band and new combustion chamber the compression ratio jumped from 12.5 to 13.5:1.

In the never-ending quest for more durability, a four-hole-piston oil jet replaces last year’s two-hole oil jet. Gone are the days of separate oil compartments for engine and transmission on the Honda CRF450R, it is now one chamber for both. A new dual-stage scavenge pump system reduces the oil volume from 1490cc to 1250cc. This helps reduce weight and simplify maintenance. The clutch is more compact and uses one less friction and one less drive plate. The drive-plate thickness has increased from 0.4mm to 2.0mm. The transmission ratios have changed for 2017 to go along with the primary-gear change. Final gearing is 13/49, one tooth larger on the rear than in 2016.

An advantage to a completely new bike is that starting from virtually scratch lets designers toss what they don’t want out the window. The 2017 intake tract no longer passes around the shock; it is now a downdraft system running above a now lower-mounted shock. As proven with other manufacturers, a downdraft system improves power and response.

Throttle pull is also lighter, helping to improve response feel. With the engine and chassis changed, the exhaust system is—ready for it? All-new as well. It still retains the dual mufflers, but they are now 78mm closer to the center of the bike while the header and shape are revised to increase flow.

Frame Work

This is the sixth generation aluminum twin-spar frame from Honda and is lighter with revised geometry and is narrower through the cross-section. While the numbers aren’t exact, the overall changes to both the frame and swingarm closely resemble the geometry of the 2008 Honda CRF450R, which many consider to be the best version of the CRF450R to date. This new frame has reduced torsional stiffness by 6.8% while lateral stiffness is unchanged. The subframe now has extruded gussets rather than forged, helping to drop the weight by 20%. The swingarm is shorter and 0.49 pounds lighter. Thanks to changes with the intake tract, the shock is now centered in the swingarm. It was previously offset to one side by 5mm.

The big news is the addition of 49mm Showa spring forks featuring A-Kit spec internals. The disappearance of the air fork isn’t going to have any riders lying on the couch of their psychologist. Good riddance, most will agree. The only real benefit to the air fork was that it saved weight over conventional spring fork (not to mention eliminating expensive springs). Honda kept the weight of the 2017 Honda CRF450R identical to the 2016 CRF450R by shaving weight in the engine, frame, subframe, swingarm and gas tank. The shock is now mounted 39mm lower in the chassis to allow the downdraft air tract to pass above the shock rather than around it. To accomplish this the shock clevis is shorter, the shock overall is shorter and it mounts 5mm lower on the swingarm.

The new titanium gas tank saves weight and helps to centralize mass. It holds the same amount of fuel (1.6 gallons) as last year. You can’t see a lot of the trick titanium tank because there is a plastic protective piece mostly covering it, but having a titanium gas tank is a first on a production bike. The plastic is, yes, all new; the radiator shrouds are longer to help draw more air over the radiators, and the graphics are in-molded for durability.

Dunlop Geomax M3S tires are standard for 2017.

Two Days Of Seeing Red

All the changes to the new chassis were aimed at increasing rear-wheel traction, lowering center of gravity and better centralizing concentration of mass. Honda also worked to retain strong cornering characteristics while improving straight-line stability. They accomplished all of the above with flying colors.

The great thing about the 2017 Honda CRF450R is that it doesn’t do anything weird, which we discovered at Alabama’s Thunder Mountain MX track, where Honda introduced the ’17 CRF450R to the media for riding. It is easy to jump on and feel comfortable and confident right away. Cornering is easy and it lays over effortlessly into ruts and holds a line nicely. We played around with fork height a bit, finding we could slide the forks down a few millimeters to increase consistency through long sweeping corners and long ruts while still retaining the ability to hug an inside line.

The Showa spring fork offers a ton of feedback and works well to keep the front wheel connected to the ground, another key to good cornering. The overall stability and balance of the CRF450R is great, letting us pick any line we wanted. The weight distribution contributes to the light overall feel on the track.

Honda lovers who wanted more from the engine will be happy. Torque is improved throughout the rpm range and peak horsepower numbers are up, all while revving higher. The improved power gets to the ground in a controlled and predictable way. Forward drive is excellent. Like last year the Honda offers three maps, changeable on the handlebars. We switched between stock and mellow depending on track conditions. As the track dried up we went to the mellow map for softer hit off idle, improving traction and consistency through the corners. The clutch changes improve the feel and improve engagement. We didn’t have any issue with fade or a mushy feel at the lever, a common problem with previous CRF450Rs.

If you want to add electric start to the CRF450R it will set you back about $650, not including a battery. Some riders at the intro struggled with starting the 2017 on the first or second kick. We learned early that pushing the kickstarter down until you feel top dead center and then coming up for a nice, smooth, full kick fires the bike up easily.

Our two days riding Monster Mountain in Alabama gave us a solid first impression of the new CRF450R. We know this for a fact: The 2017 is much improved over the 2016 and going back to a quality spring fork was a wise decision. Monster Mountain’s dirt consistency is all about traction, something we don’t see a lot of in Southern California, so we are excited to put a lot more time on the Honda and ride it at familiar tracks to learn more about how it performs and, more importantly, how it stacks up head-to-head against other 450s.

Source: 2017 Honda CRF450R: FIRST RIDE – Cycle News

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