Remember when Ricky Carmichael decimated the entire AMA professional ranks by sweeping every single moto in the 2004 outdoor National series? How couldn't you, it was only the biggest ball-stomping
performance in the history of our sport - and his second two-dozen sweep. RC first did it in 2002 on a Honda CR250R and then lost a couple motos but swept the 12 overalls in 2003 before going perfect again in '04. What does that all have to do with the 2008 CRF-R lineup from Big Red? That's when the development process began for Honda's big '08 unveiling.
There're a few noteworthy changes to the CRF450R and CRF 250R this year, but nothing as big as the introduction of the Honda Progressive Steering Damper (HPSD). Once thought of as an accessory for the off-road crowd, factory motocross teams have understood the benefits of running a damper for years - all of which have been tucked neatly out of sight. Aftermarket dampers are usually large, bulky contraptions that bolt onto the steering head and mount on or under the handlebar crossbar. Big Red has come up with a much smaller, 6.5-ounce system that attaches behind the front number plate, bolted to the re-worked steering head and lower triple clamp.
The addition of the HPSD allows for changes to the steering geometry. New triple clamps drop from 24mm to 22mm of offset which adds 2mm of trail and shortens the wheelbase by the same amount. Honda claims the bike turns quicker and with more stability thanks to the combined changes. Here's how it works.
Once the triple clamp moves beyond five degrees either direction off of center-line, the damping effect comes into play. Damping is stiffer as the unit moves away from center, but a position-sensitive circuit opens to allow for easier return to center. Also, much like a Scott steering damper, the HPSD system is speed-sensitive as well, which means the damping effect is minimal while turning at low speeds but stiffens considerably with a sudden jerk. This means that when the front end tags a square-edged hole and wants to rip out of your hands, the HPSD eases the violent jolt. However, correcting the damage and getting straightened out is doesn't require the rider to force the bars back into position.
Much like the fork that straddles it, the HPSD has 15 levels of adjustability and is rebuildable. Being able to control the damping speed will give riders another option when tailoring their suspension and handling characteristics. Honda claims that during testing, the damper allows riders to stiffen the bike's suspension because there is less jarring, deflection and movement from the front end. Whether this is true or not will be decided once we get to throw a leg over the '08 CRF models, but the implications of sharper, more stabile cornering and better straight-line performance make the HPSD one of the most intriguing upgrades of 2008.
The 450R also gets another piece of works hand-me-down technology. A multi-map CDI controls ignition mapping based on gear selection. Individual maps for first, second and third-fifth help control power delivery. A tapered exhaust header is supposed to boost low- and mid-range power while the top-end is supposed to rev out 50 extra rpm to a claimed 11,270. Honda claims 55 bhp at 9K rpm and 36.9 lb-ft. of torque at 6500. Honda also offers a usable weight figure - one that includes all equipment, required fluids and a full 1.9 gallons of fuel! Its figure of 238 is a couple pounds shy of our 2007 test bike which was a tad over 240. Perhaps those extra savings come from a new set of petal-style rotors - still 240mm each, but with those fancy ripples.
Suspension has been addressed as well with a larger cartridge rod and new oil in the 47mm Showa fork as well as stiffer springs. Revalving was in order and the shock was adjusted as well.
2008 CRF450R Specs:
Engine Type: 449cc liquid-cooled single-cylinder 4-stroke
Bore and Stroke: 96mm x 62.1mm
Compression Ratio: 12.0:1
Valve Train: Unicam, four-valve; 36mm intake, titanium; 30mm exhaust, steel
Induction: Carburetor, Keihin 41mm flat slide
Ignition: CD with three-gear-position electronic advance
Transmission: Close-ratio five-speed
Final Drive: #520 chain; 13T/48T
Fork: 47mm inverted Showa cartridge fork with 16-position rebound and 16-position compression damping adjustability; 12.4 inches travel
Shock: Pro-Link Showa single shock with spring preload, 17-position rebound damping adjustability, and compression damping adjustment separated into low-speed (13 positions) and high-speed (3.5 turns); 12.5 inches travel
Front Brake: Single 240mm disc with twin-piston caliper
Rear: Single 240mm disc
Front Tire: 80/100-21
Rear: 110/90-19
Wheelbase: 58.6 inches
Rake (Caster Angle): 26.76
Trail: 111.4 mm (4.3 inches)
Seat Height: 37.6 inches
Ground Clearance: 13.4 inches
Fuel Capacity: 1.9 gallons
Color: Red / Black
Curb Weight: 238 pounds (Includes all standard equipment, required fluids and full tank of fuel-ready to ride)2008 CRF250R
The quarter-liter thumper also gets the HPSD, 22mm offset triple clamps, three-way ignition mapping, fork and shock adjustments, works-style brake rotors and new rear fender shape. Specific to the machine are a myriad of engine adjustments. A new piston jumps the compression ratio to 13.1:1 compared to '07's 12.9:1, and moves underneath a cylinder head with new porting. Lighter valve train components, counterbalancer shaft and drive gears and revised cam timing all add to a claimed increase in power. The 40mm Keihin FCR carburetor has new settings to smooth out the delivery and the exhaust system is reworked.
Honda claims this one is ready to ride at 227 pounds which is one pound heavier than our 2007 unit. Neither machine has a listed MSRP for the time being.
2008 CRF250R Specs:
Engine Type: 249cc liquid-cooled single-cylinder 4-stroke
Bore and Stroke: 78mm x 52.2mm
Compression Ratio: 13.1:1
Valve Train: Unicam, four-valve; 31mm intake, titanium; 26mm exhaust, steel
Induction: Carburetor, Keihin 40mm flat-slide with throttle position sensor (TPS)
Ignition: CD with electronic advance
Transmission: Close-ratio five-speed
Final Drive: #520 chain; 13T/51T
Fork: 47mm inverted Showa cartridge fork with 16-position rebound and 16-position compression damping adjustability; 12.4 inches travel
Shock: Pro-Link Showa single shock with spring preload, 17-position rebound damping adjustability, and compression damping adjustment separated into low-speed (13 positions) and high-speed (3.5 turns); 12.4 inches travel
Front Brake: Single 240mm disc with twin-piston caliper
Rear: Single 240mm disc
Front Tire: 80/100-21
Rear: 100/90-19
Wheelbase: 58.2 inches
Rake (Caster Angle): 27.9
Trail: 125mm (4.9 inches)
Seat Height: 38 inches
Ground Clearance: 14.2 inches
Fuel Capacity: 2.0 gallons
Color: Red / Black
Curb Weight: 227 pounds (Includes all standard equipment, required fluids and full tank of fuel-ready to ride
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