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Racer X Films: 2020 Honda CRF250R Big-Bore Garage Build

October 8, 2020, 2:00pm
Simon Cudby Simon Cudby
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  • 2020 Honda CRF250R Big-Bore Garage Build

After over 30 years in the off-road parts business, we never stopped developing and improving our products. That’s why Polisport is an OEM supplier of some of the main motorcycle brands. We create exclusive technologies, constantly think of innovative products, and we always care for the customer. We make performance plastics!

Advertisement | Advertise with Us

For this build, we went to our old reliable: a big-bore kit on a Honda CRF250R makes it way more fun to ride, and adding Twisted Development to the mix can make it even better. Also, the Vortex ignition (mapped by Jamie at Twisted) allows the bike to rev with the big-bore. A big-bore alone in most 250Fs can add 2 to 4 horsepower, and Twisted’s mods and mapping can boost that to 7 or even 9, so it’s quite significant when ripping it around the track.

Build: Jay Clark

Video/Photos: Simon Cudby

Parts List:

Cylinder Works

3mm Big-Bore Cylinder Kit 270cc, Includes Forged Vertex Piston and Top-End Gasket Kit

www.cylinder-works.com

Twisted Development

Cylinder Head Porting and Engine Setup, Engine Mapping with Vortex ECU

www.td-racing.com

Factory Connection

Suspension Re-Valve and Setup

www.factoryconnection.com

Supersprox

Rear Sprocket, Front Sprocket, Gold MX Race Chain G520-MXT-L-120

www.supersproxusa.com

Uni Filter

Two-Stage Air Filter

www.unifilter.com

Hinson Clutch Components

Clutch Plates and Outer Cover

www.hinsonracing.com

FMF Racing

Ti Powerbombs with RCT 4.1 Mufflers

www.fmfracing.com

Dirt Tricks

Cam Chain Tensioner

www.dirttricks.com

Dunlop

MX33 Front and Rear

www.dunlopmotorcycletires.com

Works Connection

Clutch Perch Assy, Brake Caps, Works Stand II, Brake Rotating Bar Mount, Engine Plugs, Axle Blocks, Oil Filter Cover

www.worksconnection.com

DeCal Works

Semi-Custom Graphics Kit in Sparkle, Preprinted Number Plate Backgrounds in Sparkle, Graphic Guards

www.decalmx.com

UFO Plastic 

Full Plastic Kit, Mud Flap

www.ufoplasticusa.com 

P3 Carbon

Carbon Skid Plate

www.p3carbon.com

MotoSeat

Custom Cool Seat Cover

www.motoseat.com

Scar

Titanium Footpegs

www.scar-racingusa.com 

ODI

MX V2 Lock On Grips, Handle Bars

www.odigrips.com

Antigravity Batteries

Lithium-Ion Battery

www.antigravitybatteries.com

VP Racing Fuels

T4 Fuel

www.vpracingfuels.com

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    2020_Honda_CRF250R-May20-Cudby-001 Simon Cudby
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    2020_Honda_CRF250R-May20-Cudby-005 Simon Cudby
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    2020_Honda_CRF250R-May20-Cudby-007 Simon Cudby
  • Big-Bore kit used on this build.
    Big-Bore kit used on this build. Cylinder Works
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    2020_Honda_CRF250R-May20-Cudby-010 Simon Cudby
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ABOUT DECAL WORKS

Founded in 1989 by Ron and Janeen Joynt, DeCal Works has been the industry leader in pre-printed decals and custom graphics for 30 years. With a passion for racing and innovation, DeCal Works has, since its early days, focused its attention on high-quality products with great customer service.

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