Wr 250 2008

Wr 250 2008


On a cool February morning a week prior to Chad Reed's victory at the Indianapolis RCA Dome, a group of jaded motojournalists leave the warm confines of the Hilton Garden Inn aboard an armada of Yamaha WR250Rs. From the palatial campus of the Inn we ride through scenic Victorville on our way to the dirt and scrub brush of Southern California's high desert, evaluating both the street cred and off-road capabilities of Yamaha's newest dual purpose machine.

The afternoon of the same day is spent aboard the R's fraternal twin, the WR250X. Conceived and born from the same tuning fork parents, and sharing much of the same component DNA, it is apparent by sundown that the contrasts between the R and X go beyond the two models' differing cosmetic treatments.

Tom was pleasantly surprised at the minimal amount vibration coming from the hard working 250cc Thumper.Because of their historically inherent buzz and underpoweredness, I've never considered a small-displacement Thumper as the engine configuration on which to tackle the Alaska Highway. But here's where the WR250R begins to shine. Riding from the Inn I'm impressed with the minimal vibration coming from the hard working little piston pushing the 500 lbs. of combined of bike and rider weight down the freeway. In fact, the bike is so smooth I don't realize I'm riding in 5th gear. Grabbing the transmission's top cog reduces the revs to a few less per minute and it becomes apparent that riding this motorcycle for longer distances will not induce the numbing discomfort usually associated with Thumpers.

Nor am I worried about insufficient power, another innate shortcoming associated with sub-400cc machines. Horsepower figures were unavailable, but the WR has a lot more acceleration than the 250cc scooter that wheezed up hills under the additional weight of a physics book when shuttling you to class during your college career.

Citing that the demographic doesn't desire a tightly wound motor with cramped service intervals, but rather an effective engine requiring minimal maintenance, Yamaha endowed both models with a purpose-built powerplant to meet the latter criteria, while also gracing them with modern technology such as titanium intake valves, a ceramic composite plated cylinder, high lift cams, a newly designed 4-valve cylinder head and a short skirt aluminum piston. The engine also has an oil jet located beneath the piston to minimize piston temperatures.

2008 Yamaha WR250R

The Mikuni fuel-injection system utilizes a 38mm throttle body and a 12-hole injector for efficient combustion. The WR250R/X also features a radiator with a fan said to exhaust dissipated heat away from the rider (a good thing on hot days, but a not so good thing on cold ones).

As our group turns off the pavement and onto au natural terra firma another strength of the X model is revealed — suspension. The 46mm inverted cartridge KYB fork has 10.6 inches of travel and is adjustable for compression and rebound. The Soqi rear shock also has 10.6 inches of travel, is fully adjustable and features nearly 1 inch of ride height adjustability. (To reduce or raise the ride height, a lock nut must be loosened to release the bottom shock mount.)

Everyone who rode seemed impressed with the performance of the suspension, making the WR250R a competent tool for a wide variety of riders with varying degrees of skill.Pounding across the undulating desert floor the suspension seems perfectly attuned to the type of off-road riding for which the bike was made. More accomplished off-road journalists are carrying greater speeds than I, and when we stop and converse about the bike everyone seems impressed with the performance of the suspension, making the WR250R a competent tool for a wide variety of riders with varying degrees of skill.

By noonish our group rolls up to Grange Motor Circuit for lunch and a change of attire before swapping the R model for its Supermoto counterpart and etching U-shaped hieroglyphics around the corners of the popular kart track.

Cosmetically the WR250X is recognizable by the blacked-out treatment to the frame, swingarm and forks. Smaller wheels (17s on the X model vs. 21 inch front and 18 inch rear on the R), radial BT090 Bridgestone tires (the R models uses DOT approved TW301 and 302 dual-purpose rubber) and a larger front brake rotor (298mm x 4.0mm vs. 250mm x 3.5mm) augment the intended Supermoto purpose of the X model.

To match the larger front brake disc, Yamaha included a larger master cylinder piston (12.7mm vs. 11mm) to the X model. Brakes on both the X and R models were equally impressive.

Both Nicky Hayden and Max Biaggi have been photographed doing hot laps around the Grange Circuit. It's a fun, 14-turn, 0.8-mile track that instigates competition among journalists aboard equally matched Supermoto machines. And once the Bridgestone tires were up to temperature, the unintimidating nature of the 250X allowed for some close competition … err, evaluating.

2008 Yamaha WR250X

Wearing the same suspension components as the WR250R, the X's units are, according to Yamaha, "optimized for street and Supermoto riding." While stock settings may be comfortable for street use, on-track performance will definitely improve with a little stiffening of the adjustable fork and shock. The X's rear Soqi shock also features the 0.9 inch of ride height adjustment of the R model.

Weighing an inconsequential 4 dry pounds heavier than the R model (280 vs. 276 lbs.), the WR250X is great fun for recreational Supermoto track time, especially on a small circuit like Grange where the longest straight measures only 950 feet. Twisting the throttle hard coming out of corners keeps things exciting without the fear of inadvertently breaking traction as the bigger 450s are wont to do.

Being street-legal machines the X and R must pass emissions standards, so the exhaust system on both models comes equipped with a honeycomb catalytic converter and Yamaha's iconic EXUP system. Of course these items add weight and complexity to a muffler, so the word petite doesn't apply, but the aftermarket should take care of that, and Yamaha says the bike's ECU should compensate for a non-EXUP pipe. If not, a DynoJet Power Commander should do the trick.

For anyone interested in purchasing a WR250X and performing a garage conversion into a WR250R, a la KTM, Yamaha says the wheels and front brake caliper are all that's necessary and are available from your local dealer. To compensate for the smaller 17-inch rear wheel, the X model's sprocket is smaller, so you should also consider the R model's rear sprocket, which may also require a longer chain. But if your idea of off-roading is the occasional fire road or an overnighter at a KOA campground, the X model and its sticky Bridgestone Supermoto rubber will suffice.

I'd be inclined to go with the X model. As a commuter, trackday toy or weekend road warrior and for the dirt road cameo appearance the WR250X is the bike I think can do it all. But for the guy whose commute is riding the back 40 to mend a fence, check on the herd and occasionally go into town to pick up a Saturday afternoon six pack, the R model will be a better choice.

Whichever bike suits your purpose, Yamaha's WR250R/X has filled a void in the marketplace somewhere between high tech, basic performance and small capacity. The new WRs aren't fire breathing technofiles, nor are they parts-bin Frankenbikes, but for the sub-$6,000 price ($5,899 for the 250R and $5,999 for the X) and the target audience Big Blue has in mind, the R or X are attractive machines.

And as I'm watching television, typing feverishly during commercial breaks, Chad Reed laps the field up to ninth place, scoring the victory and his sixth win of the 2008 Supercross season. I realize that this should be a very good year for Yamaha – either off road or on.

Yamaha WR250R & X Technical Specifications
2008 WR250R
2008 WR250X
(click here for complete Specs page) (click here for complete Specs page)
Engine Configuration Single cylinder, 4 stroke, DOHC Single cylinder, 4 stroke, DOHC
Engine Displacement 250cm3 250cm3
Engine Cooling System Liquid cooled Liquid cooled
Compression Ratio 11.8:1 11.8:1
Valves Per Cylinder 4 4
Bore x Stroke 77 x 53.6mm 77 x 53.6mm
Valve Angle (Included) Intake 11.5° / Exhaust 13.0° Intake 11.5° / Exhaust 13.0°
Valve Train Type Bucket/shim, cam chain drive Bucket/shim, cam chain drive
Valve Adjustment Interval every 26,600 miles every 26,600 miles
Intake Valve Diameter 30.0mm (Titanium) 30.0mm (Titanium)
Exhaust Valve Diameter 24.5mm (Steel) 24.5mm (Steel)
Intake Valve Stem Diameter 4.5mm 4.5mm
Exhaust Valve Stem Diameter 4.5mm 4.5mm
Intake Valve Maximum Lift 8.6mm 8.6mm
Exhaust Valve Maximum Lift 8.9mm 8.9mm
Intake Valve Timing (0.15 mm lift) Open BBDC 64° 64°
Close ATDC 24° 24°
Duration 268° 268°
Overlap Angle 49° 49°
Camshaft Event Angle Intake / Exhaust 105° / 110° 105° / 110°
Fuel Delivery System EFI/ Mikuni/ 12 Hole Injector EFI/ Mikuni/ 12 Hole Injector
Throttle Body Venturi Size 38mm 38mm
Air Filter Type Oiled Foam / Washable Oiled Foam / Washable
Exhaust System Type Steel w/ EXUP Steel w/ EXUP
Ignition System DC - CDI (digital) DC - CDI (digital)
Lubrication System Wet Sump Wet Sump
Oil Capacity 1.5 L (1.6 US qt) 1.5 L (1.6 US qt)
Fuel Capacity 7.6 L (2.0 US gal) 7.6 L (2.0 US gal)
Fuel Reserve Amount 2.1 L (0.55 gal) 2.1 L (0.55 gal)
Recommended Fuel Premium Unleaded 91 octane (R+M)/2 Premium Unleaded 91 octane (R+M)/2
Transmission Type Constant mesh 6-speed Constant mesh 6-speed
Clutch Type Wet Multi-plate Wet Multi-plate
Clutch Actuation System Cable / pinion gear Cable / pinion gear
Clutch Spring Type Coil Coil
Number of Clutch Springs 5 5
Number of Clutch Plates 13 13
Drive Plates 7 7
Driven Plates 6 6
Primary Drive Gear (straight cut) Gear (straight cut)
Primary Drive Gear Teeth (Ratio) 78/25 (3.120) 78/25 (3.120)
Final Drive Sprocket Teeth (Ratio) 43/13 (3.307) 42/13 (3.230)
Transmission Gear Teeth (Ratios) 6th 22/28 (0.786) 22/28 (0.786)
5th 24/27 (0.888) 24/27 (0.888)
4th 26/25 (1.040) 26/25 (1.040)
3rd 29/22 (1.318) 29/22 (1.318)
2nd 29/16 (1.813) 29/16 (1.813)
1st 37/14 (2.642) 37/14 (2.642)
Transmission Overall Ratios 6th 8.109 7.921
5th 9.162 8.949
4th 10.73 10.48
3rd 13.599 13.282
2nd 18.706 18.271
1st 27.26 26.625
Frame Design Aluminum/ Semi Double Cradle/ Detachable Sub-Frame Aluminum/ Semi Double Cradle/ Detachable Sub-Frame
Rake / Trail 26.67°/ 111.0mm (4.37 in) 25.33°/ 76.0mm (2.99 in)
Wheelbase 1420 mm (55.9 in) 1425 mm (56.1 in)
Front Forks Maker / Type "KYB" / Inverted Cartridge "KYB" / Inverted Cartridge
Fork Inner Tube Diameter 46.0mm 46.0mm
Rebound Damping range 24 clicks (10 out std.) range 24 clicks (10 out std.)
Compression Damping range 20 clicks (10 out std.) range 20 clicks (10 out std.)
Spring Rate 4.6 N/mm 4.6 N/mm
Front Wheel Travel 270 mm (10.6 in) 270 mm (10.6 in)
Rear Wheel Travel 270 mm (10.6 in) 270 mm (10.6 in)
Rear Suspension Maker / Type "SOQI" / Piggy-back "SOQI" / Piggy-back
Rebound Damping range 25 clicks (12 out std.) range 25 clicks (13 out std.)
Compression Damping range 12 clicks (10 out std.) range 12 clicks (7 out std.)
Spring Pre-load Variable thread adjust nut (YZ style) Variable thread adjust nut (YZ style)
Spring Rate 80 N/mm 80 N/mm
Front Brake "Nissin" 2-piston caliper / 250 x 3.5mm "Wave" type Disc w/ "Nissin" master cylinder "Nissin" 2-piston caliper / 250 x 3.5mm "Wave" type Disc w/ "Nissin" master cylinder
Rear Brake "Nissin" 1-piston caliper / 230 x 4.5mm "Wave" type disc w/ "Nissin" YZ style master cylinder "Nissin" 1-piston caliper / 230 x 4.5mm "Wave" type disc w/ "Nissin" YZ style master cylinder
Front Wheel 1.60 x 21 spoke / Aluminum rim 17M/C x MT3.00 spoke / Aluminum rim
Rear Wheel 2.15 x 18 spoke / Aluminum rim 17M/C x MT4.00 spoke / Aluminum rim
Front Tire Bridgestone / TW-301F / 80/100-21M/C 51P (dual purpose) Bridgestone / BT090F Radial G / 110/70R17M/C 54H
Rear Tire Bridgestone / TW-302F / 120/80-18M/C 62P (dual purpose) Bridgestone / BT090R Radial G / 140/70R17M/C 66H
Overall Length 2175mm (85.6 in) 2110mm (83.1 in)
Overall Width 810mm (31.9 in) @ handlebar ends 810mm (31.9 in) @ handlebar ends
Overall Height 1230mm (48.4 in) 1190mm (46.9 in)
Seat Height Lowest / Highest 908mm (35.7) / 930mm (36.6 in) 873mm (34.3) / 895mm (35.2 in)
Ground Clearance 300mm (11.8 in) 265mm (10.4 in)
Battery / Voltage, Capacity YTZ7S (sealed) / 12V. 6.0Ah YTZ7S (sealed) / 12V. 6.0Ah
Alternator Output 14V / 350W @ 5,000 rpm 14V / 350W @ 5,000 rpm

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Wr 250 2008

Source: https://www.motorcycle.com/manufacturer/yamaha/2008-yamaha-wr250r-wr250x-review-76600.html

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