You’d never guess this CRF250R was lying in pieces, divided amongst four boxes when Jay Clark purchased it at a fraction of its original cost. Jay has a knack/obsession for resurrecting basket-case motorcycles purchased off the Internet, (aka Craigslist). His goal was to turn a CRF250R into a trail bike, loving the benefits of fuel-injection over carburation. He also likes the newer chassis of the 2010 CRF250R when compared to an older CRF250X. The downside to the CRF250R is lack of electric start. So if you have an older MX bike that doesn’t have much resale value, maybe transforming it into a big-bore off-road bike like this, what we dubbed Frankenstein CRF270R-X, could be an option. If you go the route of Jay, it won’t be a cheap path, he likes his bikes completely decked out! To make a build like this even close to worth it, you need to do a lot spinning wrenches yourself, paying shop rates for a rebuild along these lines would be astronomical. Hopefully a few key modifications from this CRF270R-X could transform your motocrosser into a worthy trail machine.
You can read the original magazine story by clicking HERE.
Dive In
Because the engine was cooked (and in pieces in a box) the first order of business was to install a Hod Rods bottom-end kit ($429), which includes a complete crankshaft, main-bearing seal kit and complete engine-gasket kit. Before the crank went into the engine, Crank Works perfectly balanced it by and adding some “heavy metal,” an added bonus if you really want a bike without vibration. Since the motor needed a new cylinder, going up in displacement was a given—and easy—with the Cylinder Works big-bore kit, which bumped the engine up to 270cc. The kit includes a forged Vertex Piston and Cometic Top-End gasket kit. Going further in the off-road power boost, a Hot Cams Stage Two cam was installed ($245) into the stock head. The stock throttle body was filthy, so Injectioneering cleaned it up and recalibrated it. They also installed a different butterfly for better response and more power. The spring tension was decreased for an easier twist at the grip.
Two schools of thought: Find a cheap basket case and spend your money building what you want, or buy something new and spend even more money building what you want. Jay Clark went with thought number one.
The installation of a Vortex ignition gave Jay the ability to easily change the mapping while increasing the rev limiter by 500 rpm over stock. Of course with engine modifications comes the need to direct the used fumes out and gone. That duty was handled by an FMF Megabomb header ($314.99) and Q4 muffler ($296.99). To keep the more powerful engine cool, especially at lower trail-riding speeds, ICW Radiators beefed up the stock radiators. They can also straighten and reinforce damaged radiators. CV4 Products supplied the silicone radiator hoses and a high-pressure radiator cap while a Motion Pro overflow bottle was there to keep the cooling juice from hitting the ground. Beneath the Hinson outer clutch cover, new Hinson fibers, steels and springs ensured strong power delivery.
The suspension was set up for 180-pound rider by Race Tech with off-road and trail riding as the target terrain. Stock spring rates were retained in combination with much softer valving. An IMS oversized tank means long adventures away from the truck don’t leave a rider stranded. While the bike was torn down to the frame a tab was welded on to the frame for the Cycra skid plate, making install clean and simple. Good brakes are as important and strong running engine, so the brake lines were flushed clean and new pads installed. Again, with the bike in pieces it was easy to replace the worn linkage and steering stem bearings with Pivot Works parts.
Clark pumped new life into this 2010 CRF250R, which included pumping it up to 270cc.
Handlebar, grips, sprocket and brake pad duties were handled by Renthal. A cool off-road addition to the CRF250R was the Pro Moto Billet Kick-It stand. Works Connection did their part in decorating and upgrading the CRF250R with a Works Connection Elite Perch, chain blocks, engine plugs, an hour meter and sweet titanium footpegs, just to mention a few items.
A trials rear tire is a nice touch for tackling obstacles.
The Pay Off
Scanning this bike, from the Cyrca plastics to the fresh Dunlop tires, it screams “I’m too pretty and precious to ride!” After an afternoon scratching up the fresh plastic, burning gas and wearing down Jay’s tires, we were impressed by the motocrosser transformed into trail bike. The power was smooth, yet much stronger than a typical 250F thanks to the big-bore and still pulled strong in the upper rpms. The added torque down low made negotiating single track easier. Softer valving from Race Tech did a great job allowing us to keep the bike planted over off-road terrain and trail hazards.
Thanks to the motocross chassis, the CRF250R trail conversion handled well at higher speeds and felt light and nimble when changing direction. We love trials tires out back for traction in technical terrain but they aren’t the best in sandy conditions. A bonus to a trials tire is that it offers up a little extra cushion, further adding to the plush feel from the suspension. Overall we really liked the character off-road of the CRF270R-X Jay Clark build and like it better than a CRF250X 99-precent of the time, but it is missing one key ingredient when it comes to trail riding all day: The electric start!
The only thing this bike is mission in the magic button—E-start. Some things money can’t buy.
The amount of modification and accessories to this basket case bike is equivalent to a kid with pockets stuffed with cash running rampant through a candy store. Not all of these additions were necessary, of course, but this is a classic Jay Clark over-the-top build. And we always dig them. After all, it’s his money and time. But there are some key takeaways from this bike. One, if your motor needs a rebuild, why not go bigger? And, two, every bike can benefit from fresh, properly tuned suspension.
It’s okay to be a bit jealous of this high-dollar older bike build, it was a lot of fun to ride and we looked fresh and clean riding it. Now if Honda would just add EFI to their CRF250X.
Anytime you can bring a motorcycle back from the dead is a good thing.
The Works
Cylinder Works www.cylinder-works.com 515/251-4070
3.2mm Big-Bore Cylinder Kit 270cc, includes forged Vertex Piston and Cometic Top-End gasket kit
Hot Cams www.hotcamsinc.com 515/402-8200
Stage-two cam shaft, cam chain
Hot Rods www.hotrodsproducts.com 515/402-8100
Complete bottom end kit, includes complete crankshaft, main-bearing seal kit and complete engine gasket kit.
FMF Racing www.fmfracing.com 310/631-4363
Q4 muffler, Megabomb header
Injectioneering www.injectioneering.com 310/953-2915
Throttle body modifications
Cometic www.cometic.com 800/752-9850
Complete Gasket Kit
IMS www.imsproducts.com 800/237-9906
Oversized fuel tank
Cycra Racing www.cycraracing.com 740/929-0188
Full-coverage skid plate, full plastic kit with Cycra Lite front fender, Pro-Bend Full Wraparound handguards
Uni Filter www.rockymountainatvmc.com 800/336-5437
Tow-stage air filter
CV4 www.cv4.net 800/874-1223
Formed silicone coolant hoses, high-pressure radiator cap
Renthal www.renthal.com 877/736-8425
Stock front 13T sprocket, rear 48T-49T sprocket, 997 Twin Walls, dual-compound grips, brake pads front and rear
Dunlop Tire www.dunlopmotorcycle.com 800/845-8378
AT81 front 90/90-21, AT81 rear 110/90-18 and D803 trials tire
Moto Seat www.motoseat.com 951/258-5229
Custom Cool seat cover and cutting of seat foam
Works Connection www.worksconnection.com 800/349-1475
Elite Perch, front-brake cap, rear-brake cap, chain blocks, engine plugs, oil-filler plugs, hour meter, bike stand, titanium footpeg set
Hinson Clutch Components www.hinsonracing.com 909/946-2942
Fibers, steels, springs and outer cover kit.
Tusk Off Road www.tuskoffroad.com 800/336-5437
270mm oversized rotor/adaptor bracket 270mm, rear disc, complete wheel set, brake-bolts kit, sprocket-bolts kit, front steel-braided brake line, rear-brake pedal, shifter
Race Tech www.racetech.com 951/279-6655
Freshened up the suspension with new fluids and seals
Pro Moto Billet www.promotobillet.com 866/466-4762
Kick-It Stand
Rocket Performance www.rocketexhaust.com 951/471-3500
Vortex X-10 ECU and mapping
Pivot Works www.pivotworks.com 515/402-8000
Linkage kit, steering-stem kit, fork and shock rebuild kits
ICW Radiators www.icwradiators.com 919/796-8084
Radiator welding, bracing seam welding
Crank Works www.crankworks.com 480/897-1746
Balance and adding of “heavy metal” to crankshaft—an added bonus if you really want a bike without vibration.
Motion Pro www.motionpro.com 650/594-9600
Overflow bottle
DeCal Works www.decalmx.com 815/784-4000
Semi-custom graphics kit, preprinted number-plates backgrounds
