Honda 2007 CRF450R

Reprinted with permission from ACP Media. (Motorcycle Trader )

In the 2006 race to launch 2007 models, Honda was the first manufacturer on the block, offering press rides in the US as early as June 2006 for the CRF450R.

Of course, there are many complex reasons that a bike will be launched early, but to the average punter, a good reason seemed that it was because not much had been done to the 2006 model. Let’s face it. They didn’t need to.

Admittedly, it weren’t broke, so fixin’ weren’t required. The 2006 CRF450R was a very complete package. Also, although Honda has massive confidence in its products, their intense race and engineering focus meant they wouldn’t let their sales-leading offroader development remain static.

Honda’s performance related changes to the 2007 CRF450R pretty much fit on the back of an envelope. The carb size increased to 41mm with a different accelerator pump and linkage, the porting massaged and the exhaust valve size decreased 1mm. Oh, and the clutch basket was upgraded, ignition was tweaked to match the carb and valve changes.

On the chassis side of things, the suspension was valved a little differently and the subframe changed to move the silencer 22mm inward to improve the centralisation of mass, the in-vogue concept sending everyone into a tizzy. Although it’s a short list, I don’t for a moment think that even one of these changes was slapped on. That would not be the Honda way.

And now for the clever thing. The whole is greater than the sum of the parts. The 2007 CRF450R is a better bike. How much better? It’s actually hard to say. Trying to isolate the effects of each change is like trying to nail jelly to a wall, but the overall impact is a bike that is simply “better” than last year. That’s not really good enough for a magazine that prides itself in analytical feedback so let’s take a closer look, at, the, eeerm, power.

The 2006 was softish off the bottom then delivered a wall of power in the lower midrange that pulled long and strong. This year, the power has been extended downward, so that the pull comes in harder off the bottom. You are still aware of the pulses – it’s no turbine – but it lays it down how, when and where you want it. This is virtually a faultless MX engine.

In trying to analyse the handling improvement we’re back to finding it hard to explain – it’s simply “better” than the 2006. If anything, it’s slightly more cooperative and the rider is better able to change line mid-corner, with less of a disagreeable scrap than occurred if you tried to do the same on the 2006.

You would normally attribute this to a change in frame flex characteristics, but I’m left scratching my head and have to conclude that moving a silencer 22mm closer to the engine has a noticeable effect. 22mm. Blimey. The slight headshake remains, but we dialled most of it out at our test track with couple of clicks less rebound and the suspension had less of the “overdamped” feeling around the mid-stroke at both ends.

Overall, our impression is of a more refined machine and let’s face it, there was no need for revolution. The MTN commentary on the 2006 picked out the reluctance to change line and the over-damped feeling suspension (just the feel, it was perfect for racing) as minor flaws. This was being incredibly picky for the sake of objective journalism. Was Honda listening?

These have been addressed on the 2007 and much like the 2007 CRF250R last month, it’s good enough to make us picky again to sound like I’m offering a balanced report. There’s rubbish airbox access, creaky rubber bar mounts, uninspiring graphics and that’s about it. Otherwise you get a sublime combination of turning and stability, powered strongly by a flexible motor. The 2007 CRF450R will be my benchmark for 2007 450 MXers.

Thanks to Anthony McLean at Blue Wing for the loan of the test bike.

Specifications
Technical Specifications
Engine
Type Liquid-cooled four-stroke four-valve SOHC single
Displacement 449cm3
Bore x Stroke 96 x 62.1mm
Compression Ratio 12: 1
Max. Power Output 38.5kW/9000min-1 (95/1/EC)
Max. Torque 47.2Nm/7000min-1 (95/1/EC)

Fuel System
Carburation 41mm Keihin FCR flat-slide carburettor
Fuel Tank Capacity 7.2-litres

Electrical System
Ignition System Computer-controlled digital capacitor discharge with electronic advance
Starter Primary kick

Drivetrain
Transmission Type 5-speed
Primary Reduction 2.739 (63/23)
Gear Ratios 1 1.800 (27/15)
2 1.470 (25/17)
3 1.235 (21/17)
4 1.050 (21/20)
5 0.909 (20/22)
Final Reduction 3.692 (48/13)
Final Drive #520 roller chain

Frame
Type Semi-double cradle; aluminium twin-spar

Chassis
Dimensions (LxWxH) 2191 x 825 x 1262mm
Wheelbase 1,491mm
Caster Angle 26° 47'
Trail 109mm
Seat Height 955mm
Ground Clearance 340mm
Dry Weight 103.2kg
Kerb Weight 108.7kg

Suspension
Type Front 47mm Showa inverted leading-axle twin-chamber cartridge-type telescopic fork with 16-step adjustable compression and rebound damping; 315mm axle travel
Rear Pro-Link with Showa damper, adjustable low-speed (13-step) and high-speed (3.5-turn) compression and 17-step rebound damping; 320mm axle travel

Brakes
Type Front 240mm hydraulic disc with dual-piston calliper
Rear 240mm hydraulic disc with single-piston calliper

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