The 2013 Honda CRF450.
FLYING INTO THE UNKNOWN
By John Basher
In my tenure at Motocross Action magazine, I’ve never been a
part of such a secret operation as what Honda planned last week. I felt
like I was told the secret to eternal life and then had to keep it to
myself. Disseminating the information probably would have led to a
stoning by Honda’s staff. For six very long days I had to hold my
tongue. But the day has come for me to reveal the biggest secret I’ve
every kept–what it’s like to ride the all-new 2013 Honda CRF450.
Zaca Station from the helicopter.
I honestly didn’t know that I would get the opportunity to do so. A month ago Honda’s PR staff sent out a cryptic email. The invitation failed to include any information regarding what Honda vehicle I would be riding. Maybe it was a new water craft, a dual-sport bike, or perhaps Honda was bringing back the two-stroke! The message did contain specific instructions to bring board shorts and work gloves. Was I going to be chopping down trees and wrestling alligators? I didn’t have a clue. I was also told to pack lightly.
This past week I met Kevin Aschenbach, the press relations coordinator, at American Honda in Torrance, California. Upon arrival Kevin was still tight-lipped about the day’s activities. It wasn’t until we arrived at Torrance airport and walked to a helicopter that I realized we were going to Catalina Island. Wrong again.
An hour later we were circling the Zaca Station motocross track. North of Santa Barbara, Zaca Station is a pristine track and a popular spot for bike manufacturers to hold press introductions. Adding everything together, I nearly sprinted from the helicopter to the Honda truck in anticipation. What I discovered was the 2013 Honda CRF450.
DISSECTING THE CRF450
The writing was on the wall–I’d be one of the first people in the world to test ride the radically new Honda CRF450. I could hardly contain myself. I circled the bike like a vulture, marveling at all of the changes that Honda made. Aside from the edgy body styling, the most obvious change is the twin-pipe design. Upon closer inspection I noticed the larger gas tank, unusual fork caps, different swingarm, and frame spars that were considerably lower on the head tube compared to the 2012 model.
WHAT ARE THE BIG CHANGES FOR 2013
* Chassis. Honda’s engineers lowered the junction point of the head pipe and frame tubes to optimize rigidity and lower the center of gravity. The rear shock mount is 14.5mm lower. The goal was to improve front and rear traction, cornering performance and stability. Honda still uses their own steering damper.
* Swingarm. The shape has been revised to increase vertical rigidity while maintaining horizontal rigidity and optimizing flex to work with the new chassis. The 2013 swingarm cross-section is slightly taller than the old design.
The 48mm Kayaba Pneumatic Spring Fork is a cool new technology.
* Fork. The CRF450 will now come with Kayaba’s all-new Pneumatic Spring Fork (PSF). This design doesn’t use main springs, which reduces unsprung weight by 1.7 pounds. It also lowers fork friction to allow quicker reaction from the front wheel over bumps and keeps the front end planted. Air replaces the main springs, making it easy for a rider to easily adjust the stiffness of the fork by adding or dropping air pressure by way of a Schrader valve on top of the fork cap. Adding or dropping 2 psi equates to a different spring rate. It’s worth noting that the PSF that comes on the Honda is developed specifically for the CRF450 (meaning that it’s not the exact same fork as what comes on the 2013 KX450F).
* Engine. Honda aimed at improving low-to-midrange power and torque without sacrificing top-end power in the Unicam engine. They did this by upping the piston compression (from 12.0:1 to 12.5:1), revising the cylinder head design (1mm larger exhaust valve size), new valve timing, adding an additional piston jet (for misting), and using a new intake air boot for optimized air flow.
* Clutch. Realizing that their previous four-spring design wasn’t working, Honda went to a six-spring clutch design. They also redesigned the transmission, revised the electronic fuel injection and ignition settings, and used a heavier flywheel for improved traction and low-end torque.
Behind that cover is a six-spring clutch. Hallelujah!
* Exhaust. Honda patented a dual diamond-shape muffler design, and they say that this design offers several advantages: (1) A shorter muffler improves mass centralization, the center of gravity, and creates a lightweight feel to improve cornering and easier side-to-side transition. (2) The twice pipes are said to increase engine performance while still meeting the (old) 94 decibel limit. (3) The dual mufflers have allowed Honda to redesign the subframe. This allows for a straighter air intake and easier filter access. Remember that Honda used a twin-pipe design on the CRF250 for four years (2006-2009).
* Body styling. Deemed as the “Ultimate Triangle Proportion” by Honda’s marketing team, the CRF450 has minimal plastics, yet maximum ergonomics. The plastic thickness has been lessened in some areas to decrease weight. The shrouds were designed to flow more air and improve radiator efficiency (note: the radiators are now slightly smaller). The gas tank capacity has been increased from 1.5 gallons to 1.66 gallons. The plastic front disc cover is now attached by two bolts, instead of having the axle collar pressed in.
THE HIT LIST
Notice where the spars are in relation to the head tube. On the previous frame the spars were much higher on the head tube.
You could spend all day reading the literature that Honda’s PR staff pumped out (and, if you’re interested in doing that, go to the bottom of this article). However, if you want to know the cold hard facts about the bike, read below:
* Honda wanted a broader powerband with more bottom-end hit (a la the Kawasaki KX450F and Yamaha YZ450F).
* The Pneumatic Spring Fork is the next thing in suspension technology (although it too is old techonolgy that every 1970s racer or Yamaha owner will remember). For 2013 the 2013 KX450F also uses Kayaba’s PSF design, and Showa has their own air fork design. Will fork springs suffer the same fate as the carburetor? They didn't the last time this was tried, but technology often moves forward by looking backwards.
* I was jumping for joy when I heard that Honda went to a six-spring clutch. The old four-spring design didn’t have enough clamping surface on the clutch pack, even with stiffer springs. Honda was toying with the idea of putting a hydraulic clutch on the 2013 CRF, but the cost would have been too great.
* Although the CRF450 has the same frame geometry as the previous generation CRF, the mass is lower on the bike and the swingarm is new. It’s no secret that MXA has bagged on the CRF450 for its uncanny ability to wiggle and headshake. However, Honda swore that they improved the bike’s handling traits by making a series of changes that, although might seem unrelated to handling, do make an impact.
Is two better than one? Honda believes in the dual muffler concept.
* Twin pipes? I thought Honda walked down this road before and reached a dead end. Although I’m not sold on the concept, I do think that the twice-pipes look cool. The question is, will aftermarket exhaust companies sell dual exhausts? The last time Honda tried this (and Husqvarna also) the aftermarket produced single-side replacements that made the twice pipes become undesirable. On the 2013 CRF450 the muffler mounting point is so far down on the subframe that it will be a challenge after aftermarket exhaust companies to use a single canister.
* I like the CRF450 body styling. You may note that it uses thesame side panel template as KTM (where the side panels run underneath the intake ducts in a design school known as "cladding"). The double mufflers will make it difficult to install pre-printed graphics because of the humps on both sides instead of one.
* Honda stated that the 2013 CRF450 will hit dealership floors in September. The price is to be determined, but Honda is planning on keeping the retail price relatively consistent with the 2012 model ($8440).
FIRST RIDE: IMPRESSIONS
The powerband has a significantly stronger bottom-to-midrange surge than the previous generation Unicam engine.
It’s a cardinal rule at MXA that we don’t write a full-blown test of an OEM bike after only a single day of riding–especially on a track that we don’t typically frequent. We try to spend months dissecting, studying, and sometimes breaking a machine before our words reach the printing press. However, since this is merely a first riding impression on a preproduction bike, I’ll have at it. I fully expect Honda to make some running changes on the 2013 CRF450 before the production models reach U.S. shores. Here are answers to some of your burning questions.
Q: DID ALL OF THE ENGINE UPDATES IMPROVE THE 2013 HONDA CRF450 POWERBAND?
A: Yes. Last year's 2012 model had a pleasant powerband, but it was far from exceptional. It paled in comparison to the Kawasaki KX450F and KTM 450SXF. Honda's engineers seemed to understand this. By adding a high-compression piston, going up on their exhaust valve size, adjusting the valve timing and changing the air boot shape, they added a healthy dose of bottom-end hit. It won’t tear your arms out of their sockets like the KX450F or Yamaha YZ450F, but there is new life in an engine that was once dead...or felt that way in comparsison to its competition.
Q: EVEN THOUGH HONDA’S CHASSIS DEVELOPMENT TEAM DIDN’T CHANGE THE FRAME GEOMETRY, DOES THE 2013 CRF450 HANDLE BETTER?
A: Yes. I was very skeptical about Honda’s reasoning behind their new swingarm and lowered twin spars. I predicted, based on raw numbers, that the CRF450 would handle identically to the previous generation CRF. Fortunately I was wrong. Whereas the old frame oversteered terribly at turn-in, understeered from center-out and required countersteering on the exit of the turn, the new frame exhibited very few of those traits. With the proper fork air pressure (I preferred a pound or two more than stock, which was initially set at 33 psi), the front end stayed up entering corners and maintained a consistent line through the turns. Granted, with too low of air pressure in the forks the diving sensation that was common with the old chassis returned.
The CRF450 feels light and nimble in the air.
Q: WHAT’S THE BIG DEAL ABOUT THE KYB PNEUMATIC SPRING FORK?
A: For starters, the lack of a main spring yields an almost two pound decrease in unsprung weight (actually, since only half of a fork spring's weight is unsprung, the air forks decrease weight by almost two pounds, but unsprung weight by one pound). That’s huge. And, because there isn’t a main spring, the internals will stay cleaner. There’s also the fact that anyone with a bicycle pump can change the stiffness of their forks by adding or dropping a few pounds of air. It takes as much time as putting air into your tires and follows the same method.
I was very surprised by the Kayaba PSF fork performance. The fork action seemed more consistent over a broader range of track conditions. The front end also maintained better contact with the ground. I swore that I was losing my mind, but then I reconfirmed my thoughts when I jumped back and forth between 2012 and 2013 models. Let me sum this answer up by saying that I can’t wait to try out this fork design on a very rough track where front end traction is pivotal. One track, perfectly prepped for a press intro, is not the end-all be-all of test tracks.
Q: ARE DUAL MUFFLERS A GIMMICK?
A: They were the last time Honda tried this. It’s hard not to question Honda’s thought process when they went with the dual mufflers. They tried to sell the twice pipe concept on the CRF250, but no one really believed that it was better. Has Honda solved the riddle of the dual mufflers? It’s hard for me to say. I’d love to test a single muffler on the 2013 CRF450, but that’s months down the road. I do know that the dually sounds louder than the eggplant-sized single can on the old bike.
Q: IS THE SIX-SPRING DESIGN THE SOLUTION TO THE CRF450’S CLUTCH WOES?
A: It certainly doesn’t hurt! No matter how good the 2009-2012 Honda CRF450 had the potential to be, the four-spring clutch shot all the goodness in the foot. Clutch abusers could chew through the previous four-spring clutch in a matter of minutes. Honda diagnosed the problem, albeit four years later, and returned to a six-spring clutch. The six springs are obviously softer than the four springs (because six springs don't have to be as stiff as four springs to achieve adequate clamping pressure). Clutch pull feels more consistent, and I didn’t have any issues burning out the clutch. The four-spring clutch made the lever feel like I was pulling the blade through mashed potatoes. Thankfully that feeling is gone.
Q: IS THE CRF450 STILL THE LIGHTEST 450 IN THE CLASS?
A: No one knows that answer...yet. However, the 2013 isn't as light as the 2012. It will be a few months before MXA can put the 2013 CRF on our amazingly accurate scale to get the real answer, since that’s how long it will take the manufacturers to release 2013 models. I do know that the CRF450 gained just under two pounds, thanks mostly to the dual mufflers, swingarm and gas tank. My guess is that the 2013 CRF450 will weigh around 234 pounds (empty tank). That’s still about four pounds lighter than the second lightest bike in the class (based on 2012 weights).
Q: DOES THE CRF450 STILL FLAME OUT?
A: The 2009-2012 CRF450's would cough and die every so often when the throttle was crack off of idle (typically in a tight turn, in the middle of a moto). During my time at Zaca Station last week I managed to kill the 2012 CRF450 engine four times. I raised the idle and it still shut off. It was irritating. The 2013 model only flamed out once, and that was without adjusting the idle. So, yes, the CRF450 did flame out, but it’s a problem that can be fixed with a simple adjustment. The heavier flywheel is a plus in this area of concern.
CONCLUSION: IS IT A WINNER?
It’s impossible for me to give any concrete opinions about the 2013 Honda CRF450. I rode the bike for a few hours on a relatively smooth track. It was also a preproduction machine. There are currently only three 2013 CRF450s in the country, and two of them were at Zaca Station.
I’ll go in front of a judge and say that I believe that Honda deserves credit for addressing the most serious issues that MXA has had with the last four years worth of CRF450s. First, the six-spring clutch was a must-do. The four-spring clutch was a deal breaker for serious racers and cost $750 to fix (via Hinson). The new six-spring clutch it worked well. Second, last year Honda stiffened up the fork springs (in a nod to what local racers had been doing since 2009). I’m enamored by the Kayaba PSF forks. They seem legitimate. Third, the dual mufflers? The jury is out on that one. The twice pipes could do what Honda say they do for the handling, but they are also the source of some of the weight gain. If aftermarket pipes save weight and make more power the eventual judge will be the consumer. Fourth, I’m pleased that preproduction CRF450 handled better than the last generation CRF450 (at Zaca Station). Hopefully nothing gets lost in translation between now and when the production bike comes out.
As I hopped in the helicopter for the flight ride back to Torrance, the calm Pacific Ocean couldn’t distract me from the excitement of riding the 2013 Honda CRF450. Honda’s staff assured me that MXA would receive a 2013 production model in August. It’s going to be a long three months spent waiting and wondering. I'd like to thank the Honda staff for the amazing opportunity to ride the pre-production CRF. Thank you! Look for a video of the first ride later today.
2013 HONDA CRF450 DEVELOPMENT
[Provided by Honda]
With the 2013 CRF450R, Honda elevates the level of performance for 450-class motocross machines. This brand-new machine features a rolling chassis with a specific focus on meeting the needs of today’s “scrub generation” of riders. Honda accomplished this through the creation of an all-new aluminum frame designed to fully integrate and attain maximum advantage from an innovative suspension package, plus a strategically engineered dual-muffler exhaust system that tucks in closely to the center of mass. Designed from the get-go as a total package that would be eminently flickable, responsive and lightweight—thanks in part to development input from multi-time champion Jeremy McGrath—every element in the 2013 CRF450R chassis has been focused on attaining class-leading mass centralization and unrivaled handling.
There’s also genuine innovation here: case in point, an all-new fork that uses air pressure in place of steel springs to save weight, create space for an entirely new and larger, more sophisticated 32mm cartridge damper piston, and deliver unmatched front-end feel and responsiveness. In short, this innovation resets the boundaries of conventional suspension technology, and this chassis has been purpose-built around this design to achieve maximum benefit. This innovative fork is matched with a new Pro-Link® rear shock that is shorter and resides lower than ever in an aluminum frame completely redesigned for the express purpose of lowering the bike’s center of gravity (CG) and enhancing handling.
Designed from clean-sheet concepts, the all-new aluminum frame carries prominent differences quite visible when compared to the previous-generation frame. Specifically, the junction of the steering head and main frame spars intersect distinctly lower on the steering head pipe, much closer to the midway point rather than toward the top as per the previous design. This change helps lower the CG, instills more tuned flex into the chassis for better front-end traction, and provides more traction feel and better cornering traits. Less readily seen yet equally important foundational design changes include maximizing the benefits of the new-generation front and rear suspension components.
The rear Pro-Link system now features a new shock that’s 14.5mm shorter than before, and it sits lower in the frame to help lower CG. New damping settings are matched to the new frame and innovative fork for a plush, yet controlled ride. In addition, from the very inception, the new frame was designed to incorporate a new two-muffler exhaust system that tucks in tightly toward the bike’s center to better centralize mass and lower the moment of inertia. This new design strikes an excellent balance between enhanced handling, maximum power and superior noise attenuation.
Manufactured by KYB, the 48mm KYB PSF® (Pneumatic Spring Fork) incorporates a startling transformation: air pressure now provides spring resistance in place of steel springs. Freed from the inherent limitations of a steel-spring design, this new KYB fork is not only an incredible 1.76 pounds lighter, there now is also more room for a new and larger piston in the cartridge damper—32mm in diameter rather than 24mm in the previous fork. As a result, this new front suspension system offers more tuning potential and returns a much more sophisticated, stable and refined fork action all through the travel. However, what’s especially noticeable are its dramatically faster responses in directional stroke transitions from compression to rebound and vice versa. This allows the front end to be significantly more responsive to changes in the terrain, and to keep the front tire in contact with the ground. The result is much better tracking, greater feel, and better traction and steering accuracy.
Another bonus: this new fork is easier to tune. Equipped with Schrader valves atop the fork caps, the standard air pressure of 33 psi can be adjusted within a range from 32 psi to 36 psi—the equivalent of installing softer or stiffer replacement springs—to accommodate varying rider weights and speeds. Air alone fulfills the pressurization needs; there’s no need for nitrogen or other inert gasses. Of course, as per usual motocross bike expectations, the fork and shock are also fully adjustable for compression and rebound damping settings.
Other chassis changes include a new aluminum swingarm that provides added rigidity thanks to taller beam height in the front and center sections for less deflection in ruts and improved corner-exit traction. Also, with the change to dual mufflers, the aluminum subframe is now lighter and shorter than before.
In the engine department, the 2013 CRF450R follows previous engine architecture, but a host of changes increase power, especially in the low-end and midrange, while also adding durability. A new camshaft with different valve timing and more valve overlap, larger exhaust valves (30mm diameter to 31mm), a new piston with a fuller dome to increase compression ratio from 12.0: to 12.5:1, new port shapes on the intake and exhaust sides for enhanced flow, and revised settings for the PGM-FI fuel injection system comprise the major performance upgrades.
For added durability, the piston skirt is now shot-peened with molybdenum disulfide to create a tougher, low-friction surface, a redesigned oil jet now gives two sources to spray cooling oil on the underside of the piston, and the transmission is a completely new, heavy-duty gearbox. Also, the CRF450R clutch is now a six-spring design for stronger clamping pressure with a lighter clutch feel, better modulation of the friction point and added durability. One other change of note is a new, slightly heavier flywheel that increases rotational inertia by 11 percent compared to the prior generation, for enhanced low-speed tractability and torque feel.
On the intake side of the engine, a new airbox and straighter airboot inlet shape improve airflow; the new airbox also makes it easier to service the air filter. On the exhaust side, the use of two mufflers allows a greater flow of exhaust gasses for more power without more noise. Also, the decision to install two mufflers allows each muffler to be shorter, and therefore closer to the bike’s center of mass. As a result, even though the two mufflers together weigh only slightly more than a comparable single, larger muffler, having the two mufflers tucked in tighter results in a measurably lower moment of inertia—the real-world payoff resulting in a bike that’s more flickable, easier-handling in the air, and more responsive in corners than it would be with a conventional single muffler hanging way out off the backside of the bike. As a small side benefit, the switch to dual mufflers allowed a 3.5-ounce weight reduction in the aluminum subframe, which is also shorter now. And the dual-muffler design allows the CRF450R to easily meet more stringent sound requirements enacted by various race-sanctioning organizations while still hitting this new machine’s performance targets.
As just one glance will attest, the 2013 CRF450R sports aggressive new bodywork and styling, with an ergonomic design that allows the rider to move around on the bike more easily. Less easily noticed, bodywork attachment points where the rider contacts the bike have been made more rigid so the rider can grip the bike more solidly for better feel and control. In addition, the rear fender now has a lift point with integrated support to make it easier to hoist the bike onto a stand, and a new tank shape integrates smoothly with the new bodywork while also boosting fuel capacity from 1.50 to 1.66 gallons to appreciably extend riding range. As a final bit of detail work, the footpegs are now 10 percent lighter, and the new design allows for better clearing in muddy conditions.
The state of the art in today’s production motocross machines has risen to immensely impressive levels of performance. The ongoing forces of mechanical evolution have irresistibly expanded all parameters of engine and chassis function to the point that huge jumps in technological advances—“silver bullets,” if you will—are now nearly impossible to attain. Still, starting with a clean sheet of paper as Honda did with the CRF450R provides distinct advantages, allowing engineers to design in whole-cloth fashion a new frame that would reap full advantage from innovations such as the air-fork and twin-muffler chassis design to carve out a performance edge that gets sharpened by the CRF450R’s myriad other detail improvements. Together they create significant gains in overall performance not possible by simply bolting different parts on an existing design. The all-new 2013 CRF450R—a large step in the evolution of one of the most successful motocross machines in history.