The CR250R needs no introduction, but we’re going to give it one anyway.

2004 CR250R Bike Build

An iconic two stroke, the CR250R is well known and well loved. It’s won just about every trophy it ever could, earning accolades for pro racers like Jeremy McGrath and Ricky Carmichael. But, like all good things must come to an end, the CR250R met its end in 2007 after R&D and production on the two stroke was discontinued. Now, all that riders like us can do is scoop up used models and fix them to suit our varying needs.

That was the story for our used 2004 CR250R. The full-fledged MX bike was on sale for a screaming deal, so we pounced on it and got straight to work. Wanting to do something a little different, though, we got to work on turning the already set up MX bike into an aggressive, off-road riding, trail-railing beast. Looking at the parts and accessories we’ve added, we think it was a total success, but we’ll let you be the judge of that. Watch the video to check out the mods, and keep reading to get a more in-depth explanation of the parts and process.

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Engine

When it comes to used dirt bikes, it always helps to pick one up that’s running and (mostly) working; Trust us – we’ve been down the roached road before. Luckily, our ’04 was running and working pretty well, actually, and the engine was only suffering from the common problems that most older CR models do.

Our engine upgrades started with the air boot intake system. There were some sealing issues with the air boot and the air filter, so we combated them with a new, aftermarket filter, and by siliconing the air boot to the air box.

With those issues taken care of, we moved on to the carburetor. We purchased our bike knowing that CR250Rs are notorious for having a finicky carburetor, and that we really didn’t want to have to deal with it. From the start, CRs are difficult to jet and get running perfectly – without even a major change in elevation or temperature. That wasn’t something we wanted to worry about or mess with, so we went straight for the Lectron High Velocity Adjustable Power Jet Carburetor Kit. These kits are hot on the market right now, and for good reason. Using a metering rod instead of jets, the Lectron kit self-adjusts for elevation and temperature, eliminating the need to play around with jetting. That alone was a huge benefit for us, not to mention the confidence we gained in our ’04 as we rode it through deserts and up mountains in the same day.

2004 CR250R Bike Build

As we continued working through the engine, we realized that our bike was already equipped with the V-Force 3 Reed Valve. The V-Force setup is a no-brainer for two stokes, especially the CR250R. Helping throughout the power range, the system not only provides more power, but also more bottom end and more top end. We would’ve added one to our CR if it wasn’t already on there – it’s something we wouldn’t want to ride a two-stroke without.

Though the V-Force system definitely helped our bikes bottom end, we still felt like it was lacking. This is a common issue for late model CRs, but our solution was adding the Boyesen Exhaust Flange in conjunction with a new, complete FMF system. Another no-brainer, the Gnarly Toque Pipe was the best suited for our type of riding. Built to be tough, the pipe offers more bottom end bark that carries well through the mid-range. We capped it all off with the Turbine Core II Silencer – the popular, forest service approved, spark arrested addition that keeps us able to ride our favorite single-track trails here in Utah.

2004 CR250R Bike Build

Trail Setup

Along with our engine upgrades, another huge facet of this built was getting our bike set up for trail riding. As we mentioned before, the CR250R is a full blown MX bike, so it needed some serious modifications to be able to manage the tighter, more technical parts of the trail. Those modifications started with the 12 oz. Heavy Flywheel Weight coming from Steahly. A weight that attaches to the flywheel, the kit helps with transition through the powerband, giving more grunt down low and more rear wheel tractability.

2004 CR250R Bike Build

To work with the new flywheel weight, we set our CR up with the Rekluse Radius CX Clutch. A full auto clutch with the best components that Rekluse has to offer – this is an upgrade we cannot rave about enough. After installing it on our ’04, we noticed a laundry list of benefits, notably eliminated stalling, increased power delivery for no slipping, and longer-lasting parts that outlast stock components. The clutch cover that comes with the kit is just an added bonus, featuring a deeper cover for more oil capacity, and a billet-aluminum composition for durability and toughness in those gnarly, off-road riding conditions. And it’s worth mentioning – with the Rekluse, you really do get what you pay for; it’s a huge investment, but when you’re likely going to have to replace those worn out parts on your used bike anyway, it’s worth it to replace them with an enduring, high-quality system like Rekluse’s.

2004 CR250R Bike Build

We had just a few more improvements to make, starting with the 3.1 Gallon Tank from IMS for more range on the trails and through the desert. Next, we added a shiny new set of radiators along with some flashy red radiator hoses. With just those few more additions, our CR’s trail specifications were rounded out, and we finally started feeling confident in its off-road capabilities.

Chassis and Drive

The first thing we tackled in the chassis and drive category was the wheelset. For looks and performance, we went straight to Tusk. Their Impact wheels are second to none, and their 18” rear wheel gave us the setup and forgiveness we needed for our type of off-road riding. Tires were the next step, and we opted for Michelin’s Starcross 5 Medium Terrain Tires. A personal favorite, these tires are long lasting with the same, dependable traction throughout their whole lifespan, even in a variety of terrains. With some Bridgestone Heavy Duty Tubes installed in between, our wheelset was complete.

2004 CR250R Bike Build

Driving our fresh new wheelset is the Primary Drive Chain and Sprocket Kit, complete with a steel front sprocket, alloy rear, and gold X-ring chain. Not only do they look trick, the Primary Drive kits are long lasting, low maintenance, and definitely a bang for your buck.

One of the favorite chassis upgrades we made was a kickstand from Trail Tech. If there’s one thing on the trail that gets annoying, it’s holding our bike every time we stop. With the easy-to-install, easier-to-use kickstand, that nuisance was eliminated, and we couldn’t be happier.

2004 CR250R Bike Build

Next, we mounted the GPR V4 Stabilizer under our bars. The stabilizer may be out of sight under there, but it definitely isn’t out of mind; GPR’s kit makes a huge difference not only on a single track where we nail rocks and roots, but also just typical off-road riding, helping to keep higher, more consistent speeds. Inspiring confidence, the setup reduces headshake and makes us feel more comfortable, and therefore more stable, wherever we ride.

It’s also important to mention the brake system on our CR. As with any other bike this age, the brake system was not up to snuff with the power and performance of new bikes. So, we wanted to get our CR’s brakes up to par and, since the brakes that came with it were worn out anyway, we replaced everything with our go-to brand for brake components – Tusk. With steel braided brake lines for the front and rear, along with some new brake rotors, our stopping power and leverage were drastically improved. Altogether, the new brake parts really brought our bike to the level of newer models.

2004 CR250R Bike Build

Protection

To protect all of our shiny new upgrades, we added a slew of accessories. Starting with our new brake components, we added a Tusk Billet Rear Disc Brake Guard and a Works Connection Caliper Guard. Moving forward, we installed the super tough, nearly indestructible Ricochet Off-Road Skid Plate to protect our engine. From there, Devol’s Aluminum Radiator Guards were the best option for our new radiators. Not only do the guards brace the radiators and keep them straight, they also protect the fins and keep the radiator working like it should. The last protective measure we took was the Tusk D-Flex Handguards. Another personal favorite, the handguards offer the durability, quality, and everything else we need in a set of full wrap around handguards.

2004 CR250R Bike Build

Rider Triangle

With our CR250R running well and well protected, it was time to fine-tune its performance, starting with the rider triangle. The rider triangle refers to the rider’s three points of contact on the bike – the bars, the pegs, and the seat. For the bars, we opted for an oversized set of Pro Taper EVOs. The bars give good flex for trail riding and, with some Pro Taper Pillow Top Grips on top, the bars were that much more comfortable. Grippy and sturdy, the pillow tops helped to cut down on the vibration of our older two stroke.

2004 CR250R Bike Build

Another thing that helped on our bars was the Magura Hydraulic Clutch. Your bike doesn’t even need to have the Rekluse clutch for the Magura system to be a huge improvement over the stock clutch setup. With an unbelievably easy clutch pull, Magura’s hydraulic clutch consistently enhances our comfort on longer rides and keeps us from getting fatigued as easily.

Moving down to the feet, we swapped out the foot pegs that came on the bike for the Tusk Billet Race Foot Pegs. Switching out the worn – or maybe even stock – foot pegs on these older bikes for an aftermarket offering is a great way to enhance control and feeling every ride. The wide foot bed and super grippy feel on the Tusk pegs made them the best fit for us. And, since we were already down there, we also added a new shift lever and brake pedal from Tusk as well, just to round out our foot upgrades.

The seat cover was last, and it was an easy choice. We’ve run the Rocky Mountain ATV/MC Pro Series Seat Cover before, so we already knew that it was perfect for the type of riding we wanted to do. The cover’s grip helps keep us in place on the seat, and the colorway really played into the look we wanted for our CR.

Suspension

Some other fine-tuning we had to do was with the suspension. Fortunately, the setup our ’04 came with was actually pretty good. All that we did was freshen everything up – setting the sag and giving the clickers a few small adjustments. That quick touch up worked great for us, and has been working well with everything we’ve thrown at our bike.

2004 CR250R Bike Build

Aesthetics

Last but not least, we had to add some bling to our new and improved CR. It wasn’t running like an ’04 anymore, so we didn’t want it to look like one. With the MX Restyle Kit from Polisport, our bike’s plastics were updated to this decade, and it made a huge difference. With a custom set of matte Attack Graphics on there, our color scheme was completed, and it really turned out fresh.

The bike was finished off with some red anodized parts – just the cherry on top – giving our CR that bling factor we were after.

2004 CR250R Bike Build

In the End

After finishing our bike and taking it on some grueling rides, we were impressed with its handling, performance, and overall feel. This ’04 has never run better, and it’s well on its way to becoming our go-to trail riding machine. Check out the table below for a better look at the parts we used in this build, and be sure to like and subscribe to our YouTube channel to never miss a build like this, plus tons of other cool content.

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Tell Us What You Think

Do you like how our CR250R turned out? Would you have done anything differently? Let us know in the comments below!

Parts Available at Rocky Mountain ATV/MC

Pro Taper Evo Bars Pro Taper Pillow Top Grips Tusk Billet Bar Clamp
Pro Taper Evo Bars Pro Taper Pillow Top Grips Tusk Billet Bar Clamp
Tusk D-Flex Pro Handguards Tusk Aluminum Throttle Tube GPR V4 Fat Bar Stabilizer Kit
Tusk D-Flex Pro Handguards Tusk Aluminum Throttle Tube GPR V4 Fat Bar Stabilizer Kit
Tusk Front Brake Line Tusk Rear Brake Line Magura Hydraulic Clutch
Tusk Front Brake Line Red Tusk Rear Brake Line Magura Hydraulic Clutch
Tusk Brake Lever Ricochet Offroad Skid Plate Tusk Skid Plate Foam
Tusk Brake Lever Ricochet Offroad Skid Plate Tusk Skid Plate Foam
Polisport Lower Fork Guards Polisport MX Restyling Kit Works Connection Rear Caliper Guard
Polisport Lower Fork Guards Polisport MX Restyling Kit Works Connection Rear Caliper Guard
Boyesen Clutch Cover Boyesen Ignition Cover Polisport Mud Flap
Boyesen Clutch Cover Boyesen Ignition Cover Polisport Mud Flap
Tusk Billet Rear Disc Brake Guard Tusk Linkage Guard Tusk Oversized Front Brake Rotor
Tusk Billet Rear Disc Brake Guard Tusk Linkage Guard Tusk Oversized Front Brake Rotor
Tusk Rear Brake Rotor Tusk Brake Rotor Bolt Kit Tusk Rear Brake Clevis
Tusk Rear Brake Rotor Tusk Brake Rotor Bolt Kit Tusk Rear Brake Clevis
Steahly Heavy Flywheel Weight 12 oz. Rekluse RadiusX Clutch FMF Gnarly Torque Pipe
Steahly Heavy Flywheel Weight 12 oz Rekluse RadiusX Clutch FMF Gnarly Torque Pipe
FMF Turbine Core II Silencer Boyesen Exhaust Flange Primary Drive XTS Front Sprocket
FMF Turbine Core II Silencer Boyesen Exhaust Flange Primary Drive XTS Front Sprocket
Primary Drive Rear Sprocket Primary Drive Gold X Ring Chain Primary Drive Sprocket Bolt Kit
Primary Drive Rear Sprocket Primary Drive Gold X Ring Chain Primary Drive Sprocket Bolt Kit
Primary Drive Rear Chain Guide Tusk Air Filter Bolt Trail Tech Kickstand
Primary Drive Rear Chain Guide Tusk Air Filter Bolt Trail Tech Kickstand
Tusk Billet Foot Pegs Tusk Folding Shift Lever Devol Extreme Radiator Guards
Tusk Billet Foot Pegs Tusk Folding Shift Lever Devol Extreme Radiator Guards
Trail Tech Vapor Speedometer/Tachometer Lectron High Velocity Adjustable Power Jet Carburetor Kit with 3 Inch Cable IMS Fuel Tank
Trail Tech Vapor Speedometer Tachometer Lectron High Velocity Adjustable Power Jet Carburetor Kit 3 Cable IMS Fuel Tank
Tusk Gas Cap for IMS tank Attack Graphics Custom Alloy Kit Tusk Billet Bling Kit
Tusk Gas Cap for IMS tank Attack Graphics Custom Alloy Kit Tusk Billet Bling Kit
Rocky Mountain Seat Cover Devol Lowering Linkage Arm Tusk Impact Wheel Kit
Rocky Mountain Seat Cover Devol Lowering Linkage Arm Tusk Impact Wheel Kit
Michelin StarCross 5 Medium Terrain Tire Bridgestone Heavy Duty Motorcycle Tube Tusk Rim Lock
Michelin StarCross 5 Medium Terrain Tire Bridgestone Heavy Duty Motorcycle Tube Tusk Rim Lock