Project KX250F: The Ride

Article by Michael Lindsay/ photos by GuyB/ video by Andre Barbosa.

KX250F Project Bike Wrap-Up — More Motocross Photos

Building something this in-depth is both time-consuming and rewarding, of course the major reward being the first time you ride it (unless you're like me and you drool over fancy parts, if so you enjoy the build as well). Setting out with such lofty goals takes a lot of research and advice, so always make sure you have your "ducks-in-a-row" per se. If you're ever plan to do something like this yourself, remember one thing, you're building this bike for enjoyment. Don't get angry and start talking to your tools... or throwing them.

Now our goal was simple, build a better dirt bike in every way. Well it isn't as simple as it sounds, but as I tore down this KX250F to a frame I kept telling myself that so it would keep my confidence high. If you checked out the engine build article, then you know there was quite a bit of time spent on the internals of this beast. Once the bike was re-assembled though and the day had arrived, it was time to see if it was worth the wait. The first few laps were interesting, it had been awhile since I had swung a leg over a modified 250F, let alone one with this much work. So the first few laps were quite the adjustment as the changes to the motor characteristics were obvious. It pulled harder down low, revved quicker and pulled farther than the stocker, until it finally hit the rev-limiter. Sounds like we hit our goal, right? Beyond the arm-wrenching speed was some welcomed features, things that also made the bike easier to ride. With the additional bottom-end power the bike was easier to carry a gear higher in almost every corner, keeping the rear end tracking, and the tire spinning less. This also eliminated some of the need to shift coming out of a corner into an immediate obstacle, as it quickly pulled into its excessive mid-range power. Not to say this is some magical mini-450 with no shifting required, but it definitely makes certain sections easier. The overall inertia of the engine had changed as well, with the engine feeling freed up, it was easier to place into ruts. The lessened engine braking allowed the bike to float across chop, instead of dragging itself into it.

Beyond the motor, we addressed the rest of the bike. We took care of the brakes to slow it down, adding larger waved-rotors from Galfer, new pads, and a billet front brake caliper from Ride Engineering. Handling wise we went Dunlop's new MX32s which we recently tried out at their intro, we chose them because of their performance on a wide-range of terrains. I'm not exactly the tallest person out there, so the subframe was notched (easy to do on the current Kawasakis) to lower it 10mms. A linkage and bell-crank from SDI was installed to slightly lower the bike but also change the curve on the shock. Up front there was a set of X-Trip triple clamps, outside of their adjustable offset they also offer six different bar positions. So I was able bring the bars closer, and set in a slightly lower set of Renthal bars (996 bend). Having a bike tailored to your height and riding style brings a whole new level of comfort. It's also a nice change compared to our usual routine of jumping on anything, with different height and bends of bars, sag heights, footpegs, levers etc. Although jumping on random bikes can sometimes help you find a new bar bend, grips, or maybe general setup you like better and can add to your own ride.

At the end of the day there was one thing that stood out upon anything else, the smile on my face. I sincerely hope that everyone gets the chance to build a bike piece-by-piece as they want it, at least once. Something that suits you and brings the same smile to your face when you swing a leg over it. But If you're like me, you may think, "What if I hang it from the ceiling to stare at? Hmmm..." Check back soon for our next project bike and for our continued product evaluations and reviews.

We also have some riding footage from our shake down test out at milestone for your viewing pleasure, courtesy of Andre Barbosa. Below that is a list of the products we used in this build along with links with more information about them.

Project KX250F: Shake down - More Motocross Videos

Video by Andre Barbosa

You can check out the original motor build article from this bike here: Project KX250F

CP Carillo - - (949-567-9000) Piston and Rod kit $595.00.

FMF - - (310-631-4363) 4.1 RCT Exhaust with Mega-Bomb header $899.99.

Hinson - - (909-946-2942) Complete Billetproof clutch kit with cover $1094.99.

Enzo Racing - - (714-541-5218) Suspension re-vavle $180.00 front and $180.00 rear/ re-spring $112 fork springs and $122 shock spring (depends upon model, and parts used).

Decal Works - - (815-784-4000) Custom graphics kit $269.90.

RAD Manufacturing - - (435-574-2537) Wheelset with Eagle series light-weight hubs front $269.95 and rear $329.95.

Renthal - - (877-736-8425) Twinwall handlebars $119.95, kevlar grips $19.95, sprockets front $25.95 and rear $69.95

Galfer - - (805-988-2900) Front $395.99 and rear $138.99 brake rotors and brake pads.

Works Connection - - (530-642-9488) Engine plugs $39.95, factory 4 stand $119.95 , holeshot device $109.95, radiator braces $79.95, Axle blocks $49.95, front $27.50 and rear $24.95 brake master-cylinder caps.

ICW - - (919-795-8084) Reinforced radiators $60.00 per radiator.

Lightspeed - - (714-990-5767) Carbon fiber skid plate $199.95, case-saver $49.95, rear chain guide, and footpegs $229.95.

X-Trig - - (909-949-4155) X-Trig triple clamps $799.99.

Moto Seat - - (951-677-8325) Custom ribbed seat cover $64.95.

Motorex - - (763-417-1377) Oil and other lubricants.

Dunlop - - (800-845-8378) Geomax MX32 front $127.95 and rear tires $143.95.

VP Fuels - - (210-635-7744) T4 Fuel $70.99 for 5 gallons.

RK Excel - - (760-732-3161) A60 rims and chain.

Injectioneering - - (310) 953-2915) Thottle body mods $295.00.

Crank Works - - (480-897-1746) Cranks services and custom work.

Tokyo Mods - - (888-457-9403) Head porting, manual cam-chain tensioner, DLC buckets, and Vortex box mapping.

SDI - - (714-464-2050) Linkage and bell-crank.

Boyesen - - (800-441-1177) Supercooler kit.

Ride Engineering - - (800-805-1516) Billet brake caliper $374.95, steel-braided brake line $69.95, rear brake clevis $44.95.

Cycra - - (800-448-1223) Full plastic kit $169.95.

ARC - - (714-543-0362) RC-8 clutch perch with composite lever $184.95, composite brake lever $69.95.

CV4 - - Tank blanket $74.95, $189.95 Radiator hoses, and 2.0 radiator cap $20.65.

Del West - - (800-990-2779) Flat-faced Ti Valves.

Hotcams - - (515-402-8005) Stage 1 Cams.

Xceldyne - - (336-475-0201) Valve spring kit.

DT1 - - Air filter, air filter cage, and oil filter.

RCR Transmission - (407-880-6163) Transmission undercutting and tumbling $300.


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