The official info on the most talked about bike of the upcoming model year, Honda's 2017 CRF450R, has finally been revealed. After spying it through a fence a few weeks ago, we're able to confirm a lot of what he had learned the other day, along with surprising us with some goodies we didn't expect.
Starting off with the most common question that everyone has, what about the forks? Yes, the 2017 CRF450R does come with spring forks. More specifically, a production version of Showa's latest generation twin-chamber A-kit level suspenders. These forks feature 49mm lower tubes, 14mm damping rods, and 25mm pistons; the same stuff used in Honda's own works level forks just a few years ago. Having these forks on a production bike are a huge step, namely because of the cost involved in production. Just to confirm for those still scratching their heads, yes, these forks have springs in both sides and no air chamber to fiddle with.
Probably the second most common question on people's minds is, does it come with electric start? Not quite, but the rumors were true, and it will be an optional part. It does comes stock on the new CRF450RX, and you can get the electric starter and wiring harness as separate part numbers for the R model. This kit doesn't have an exact price yet, but is expected to cost around $650 and doesn't include a battery. The quality and weight of battery will depend on how much you'd like to personally spend. The electric starter will be fairly straightforward to install, as there are mounting points on the back of the engine case for it, along with a plug in the backside of the kickstarter housing, which can be removed to insert the drive mechanism from the new electric starter. Optionally, the kickstart mechanism, shaft, and lever could be removed, then plug that case area to lose a bit of the weight gained by the electric starter.
Here's a massive talking point for the new CRF450R is in the powerplant. While the engine is technically all new, there are a few key changes. One, the intake is a downdraft design, similar to the Yamaha, but without spinning the cylinder head around. Due to a lower-mounted shock position, they were able to get their intake tract above it, giving it a straight shot into the cylinder head (without having to wrap around the shock first) and allowing for less intake angle while entering the combustion chamber. To match this, the valve angles have been decreased, and the valves enlarged by 2 mm.
Beyond this, they've also bumped the compression ratio from 12.5:1 to 13.5:1. Along with more aggressive cam lift and duration, this engine pumps out quite a bit more power. How much? According to the American Honda staff, the 2016 model produced 54.5 horsepower to the crank on their engine dyne, while the 2017 engine is putting out just about 60 horsepower on the same engine dyno. Equating to roughly a five-and-a-half (5.5) horsepower gain! Putting the Honda back into a more competitive fight in pure numbers when compared to the competition.
These diagrams and models will give you better insight into the work Honda put in on the intake tract and overall design.
Because of this new intake design, the shock layout needed an overhaul. The top mount for the shock was moved 39mm father down in the frame, the angle was changed, along with the shock reservoir design. In the end, with a lower hanging linkage as well, they were able to keep a similar stroke length to the 2016, even with the massive move.
A look at the new swingerarm also shows the work that went into centering everything possible on the new bike.
I think most would agree that another large surprise is the fuel tank. While we originally guessed that it was aluminum, Honda took it to the nth degree and actually stamped the tank out of titanium. Purely onboard for weight reduction, this tank helped trim the Honda back to its previous weight, after the Showa spring forks packed on a few extra pounds.
Moving farther down into the engine we can see some of the changes to create a more compact engine. Surprising is Honda's change from two separateoil systems, which they've long used in their CRF line, to a single oil system,with lowering the overall oil quantity in the engine.
Jumping back into performance, the Honda crew had an interesting pitch at the event, namely about getting the ultimate holeshot. A lot of focus with the gained power and chassis changes have helped towards directly increasing the bikes performance on the starting line. By how much? Well, they broke it down for us in a simple chart to show what their personal testing against the 2016 model had revealed. To put it basically, they had decided that in the first three seconds of the start, their new bike was worth one-and-a-half bike lengths over the outgoing version.
Keep scrolling down to dig into the tech specs, along with more breakdowns of each new area of the bike and more photos/diagrams.
Specifications - 2017 Honda CRF450R
- Engine Type: 449.7cc liquid-cooled single-cylinder four-stroke
- Bore x Stroke: 96.0mm x 62.1mm
- Compression Ratio: 13.5:1
- Induction: Programmed fuel-injection system (PGM-FI); 46mm throttle bore
- Ignition: Full transistorized ignition
- Transmission: Constant-mesh 5-speed return
- Final Drive: 520 chain; 13T/49T
- Valve Train: Unicam® OHC, four-valve; 10.0mm intake, steel; 8.8mm exhaust, steel
- Front Suspension: 49mm fully adjustable leading-axle inverted telescopic Showa coil-spring fork; 12.0 in. travel
- Rear Suspension: "Pro-Link swingarm system; fully adjustable Showa single shock; 12.4 in. travel.
- Front Brakes: Single 260mm hydraulic disc
- Rear Brakes: Single 240mm hydraulic disc
- Front Tires: Dunlop Geomax MX3S 80/100-21 55M with tube.
- Rear Tires: Dunlop Geomax MX3S 120/80-19 55M with tube.
- Rake (Caster Angle): 27°22’
- Trail : 116.0mm (4.6 in.)
- Seat Height: 37.8 in.
- Ground Clearance: 12.9 in.
- Wheelbase: 58.3 in.
- Fuel Capacity: 1.6 gal.
- Color: Red
- Curb Weight (Full tank of fuel, lubricants, tires, ready to ride): 243 lbs.
- MSPR: To be Announced.
Cole Seely: Riding the 2017 Honda CRF450R - More Motocross Videos
Honda Press Release Below:
Since its 2002 introduction, the CRF450R has earned an enviable racing pedigree, and the 2017 edition is the best yet, with superior technology and style. Riders know that the most important part of any motocross race is the start, and the new CRF450R Unicam® engine has been developed to achieve overwhelming performance in the first 100 feet of battle, offering increased power output but also allowing unparalleled traction. And while arriving to turn one first is significant, winning requires staying in front for the entire moto, which is why Honda engineers designed an all-new chassis with reduced weight and centralized mass. The result is a machine that is at once fast, reliable and forgiving, and that allows riders to more easily extract maximum performance, consistently turning low lap times while simultaneously taxing their bodies less.
Engine/Drivetrain
- Downdraft intake layout increases power by reducing resistance, improving air-charging efficiency.
- New combustion chamber with higher compression ratio, decreased valve angle for greater efficiency.
- Use of finger rocker arm allows increased valve lift while retaining compact Unicam layout.
- Coils on valve springs have oval cross-sections to allow low engine height.
- New port layout with straighter flow for increased efficiency.
- New piston with improved combustion efficiency.
- Diamond-like carbon (DLC) on piston pin, rocker arm reduces friction, increases durability.
- New, compact dual muffler with more-gradual pipe bends for smoother exhaust flow.
- Shallower clutch assembly with fewer, thicker plates for narrower engine width.
- Kick start standard, with electric start available as an accessory.
Chassis/Suspension
- New layout allows improved traction through concentration of mass, lower center of gravity.
- New, lighter sixth-generation aluminum twin-spar frame with revised geometry; allows improved cornering performance through reduction of torsional stiffness (lateral stiffness is unchanged).
- New, lighter swingarm assembly with increased vertical and lateral stiffness.
- New rear-suspension location lowers center of gravity.
- Narrower cross section (down 30mm at radiator shrouds).
- Aluminum rear subframe with extruded gussets for lighter weight.
- Showa fork is now 49mm (up 1mm), with coil springs replacing air system.
- New, lighter titanium fuel tank.
- The kill switch/ignition map adjustment switch has been combined into one unit for reduced weight.
- Dunlop Geomax MX3S tires.
- Plastic bodywork with a smoother layout and have film-insert graphics for improved appearance and durability.
- The new front fender shape allows a more efficient air path to radiator.
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