The Honda CRF450R is an iconic bike not only in Honda’s lineup, but also in the history of four-strokes. In 2002, Honda dropped the first ever 450cc race bike – the CRF450R – and the model completely changed the game as far as competitive 4-stroke race bikes go. After a few years’ worth of refinements and upgrades, the model quickly became the cream of the crop, with 2005-2008 standing as the golden years for Honda’s 450 race bike.
So, when we saw a totally roached ’05 CRF450R go up for sale, we got an idea: What if we restored this revolutionary bike to its former, golden-era-racing glory? We knew it would take a lot of blood, sweat, and TLC, but we were determined to have a reliable, competitive race bike by the time we were done. So that’s what we did, and we even filmed it all in an in-depth, totally comprehensive video series called Roached2Racing. Here, we’ll just go over the parts and accessories we added, but you can use this article and that video series as a resource and fun way to look at restoring an old four-stoke. Check out the stand-alone build video below, and keep reading for an explanation of all of the mods we made!
VIDEO
Engine
The first thing we tackled on our roached-out Honda was the engine. We picked up the 14 year old bike knowing it didn’t run, so we were prepared to go through the engine from top to bottom. Starting with the top end, we replaced the worn out piston, bearings, crank, seals, and gaskets with the Wrench Rabbit Engine Rebuild Kit. Next, we made sure our head got some fresh valves, then moved down to the bottom end to replace those bearings, too. With some all-new transmission components added, our Honda was officially running again. There were still a few more engine issues we wanted to address, though – starting with the clutch.
With how worn the other engine components were, we weren’t surprised to find a trashed clutch basket and fried clutch plates in our Honda. We decided to go with all aftermarket replacements, first adding the Hinson Momentum Clutch Basket. A common problem with older 450 four-stokes is stalling and flaming out, but the Hinson clutch is an effective solution. Essentially the same as a flywheel weight, the weighted basket adds rotating mass to the engine, addressing the problem and adding some extra performance in the off-road, technical, gnarly conditions we want to ride our CRF in. With the Tusk Competition Clutch Kit and Billet Proof Hinson Clutch Cover added, our clutch was like new, refreshing the look of our engine while toughening it up a bit.
The final clutch upgrade we made was further up the bike with the Magura Hydraulic Clutch. Older 450s are notorious for having a hard clutch pull, and that can really take a toll on you after you after a few hours of riding or racing. To combat that fatigue, we made the switch to a Magura system. The easy installation (the system is essentially plug-and-play) provided a night-and-day difference in clutch-pull. Magura’s consistent, one finger pull is such an improvement from the stock setup and was easily one of the top upgrades we made to our CRF.
Continuing up the bike, we noticed that our stock radiator hoses were leaking. This was an easy fix to make, and we replaced the old hoses with Mylers Radiator Hose Kit. It was a must-have adjustment to make, while still serving as a nice accent to our engine. We also decided to add an hour meter. With our fresh engine upgrades, we’re not taking any chances with maintenance. An hour meter helps keep us on a regular maintenance schedule so that we can keep our new bike in top condition.
To round out our engine upgrades, we made some final adjustments to the intake and exhaust. The old air filter was replaced with a Tusk First Line Air Filter, and the carburetor was rebuilt with the Tusk Carburetor Repair Kit. With our new and improved intake, it made sense for our exhaust to follow suit. The stock header was munched, anyway, so we installed a full FMF system, including the spark-arrested Q4 silencer. Lightweight, durable, and dang good looking, the full system was the perfect addition to our refreshed engine.
Altogether, the engine upgrades all stayed within stock specs, keeping the bike reliable and still really fun to ride.
Chassis and Drive
As with any bike this age, parts are likely going to be worn out, loose, and ready for replacement. That was true for all of the bearings on our 2005 CRF. We kicked off our chassis and drive upgrades with a whole set of new bearings from Pivot Works. New steering stem, swing arm, shock, linkage, and wheel bearings revolutionized our bike’s feel and helped get everything working and moving properly again.
Once the new bearings were added, the next moving part we had to tackle was the wheels. The front wheel that came on the bike was cracked, giving way to seized spokes and nipples. Repairing them wasn’t worth the manpower, not to mention the safety concerns, so we opted for a full wheel replacement. We knew that we wanted our bike to have a red and black color scheme, so we decided to build a custom Tusk Impact wheel set with black rims, black spokes, and red hubs. The new wheels provided just what our bike needed – long-lasting performance with some extra flash.
When it came to the tires, we didn’t hesitate. A personal favorite of ours is the Dunlop MX52, so that’s what we mounted on the front and rear. They looked great on our new wheels and are an awesome option for desert racing - something we plan on doing with our rebuilt CRF450R. That’s why we also added some Bridgestone Ultra Heavy Duty Tubes. Sure, they add a little extra weight, but it’s well worth the protection from flats during a race or typical off-road riding.
Next up, our bike was in desperate need of a new chain and sprockets. Adding the Primary Drive Chain and Sprocket Kit with an X-ring chain and stock gearing was the best option for us. The kit even came with a counter shaft spacer, giving us just enough to safely run the X-ring chain without rubbing the case.
The brakes on our Honda needed a little TLC, too. All of the brake components were still stock – old fluid, squishy brake lines, worn rotors, and shot brake pads. It all needed to go, and it all got replaced with top-of-the-line Tusk parts. With steel braided brake lines, stainless steel brake rotors, and sintered metal brake pads, our bike had improved stopping power comparable to even that of newer bikes.
Protection
Protecting our engine upgrades was the next obvious step for us. We’ve found that investing a little money in protection items at the start saves headaches and more costly repairs down the road, so we didn’t hold back on our upgrades. First up was a skid plate. Acerbis has a plastic option that offers great coverage for both the undercarriage and the side of the engine, along with quick installation and removal for easy maintenance.
When we bought the bike, the radiators were bent and mangled. We did our best to straighten them without doing more damage, and were ultimately able to salvage them. To prevent them from going back to their old crooked ways though, we added some Works Connection Radiator Braces. The braces are a great preventive measure, one that we think is well worth the investment as they will save us the time and money of trying to straighten bent radiators, or purchase new ones, down the road. An extra preventative measure we took with the radiators was swapping out the original radiator cap for the Tusk unit with a built-in temperature gauge.
To further protect our bike, we also added the Rear Billet Disc Guard from Tusk. It’s a huge upgrade from the stock plastic (if your bike still has it), and it nicely covers all of your bike’s brake components.
Last but not least, we wanted a way to protect our hands and our levers. We opted to install our favorite wrap-around style handguards, the Tusk D-Flex Pro Handguards. Designed to be sturdy and durable with a safe, close fit, the handguards are a must-have for any form of off-road riding and racing.
Rider Triangle
Once the bike was consistently running and well protected, we started fine-tuning the performance. The process began with the rider triangle, or the three parts of the bike the rider touches: the handlebars, the pegs, and the seat. Now, Hondas have always been known for having spot-on ergonomics right off the showroom floor, and this 2005 model is no different. That being said, small, personalized adjustments to the triangle can make noticeable improvements to your bike’s feel and performance.
Starting with the handlebars, we installed a set of ODI CFT Podium Handlebars in the Country Boy Bend. This bend measures up closely to the Renthal 927 bars that came stock on the CRF450R in 2005, and it’s a bend that is the perfect blend of comfort and forgiveness for our riding style. To further trick-out the bars, we added some fresh ODI V2 lock-on grips. Easy to install, easy to remove, and extra comfy, the grips were a flashy accessory for our new bars.
Next, we shifted our focus to the foot pegs. On our bike, everything by the feet was stock, including the foot pegs, shift lever, and brake lever. We decided to replace everything. The stock pegs were ditched for the Tusk Billet Race Foot Pegs, and, trust us, the wider foot bed and extra grip were well worth it. Along with the new shift lever and brake pedal, our bike had noticeably improved feel and control.
To complete the triangle, our bike’s seat got some refinements. Under the old seat cover was the stock foam, still soft and in decent condition. So, with the original foam, we installed a new Factory Seat Cover from Attack Graphics. It grips when you’re on the gas, is consistently comfortable, and had an option that played right into our red and black color scheme – it was the perfect fit for our bike.
Suspension
Though Hondas are also known for having great stock suspension, our stock setup needed some freshening up. We decided that, before just sending the suspension off to be professionally tuned, we wanted to see what we could do on our own with the stock components. So, we went through the forks and shocks, added all new Pivot Works components, and replaced the oil. After spending some time adjusting the sag and clickers, we were pleasantly surprised with how well-sprung the bike felt and how well it rode in our preferred off-road conditions.
Bling Bling
With the bike fully functional and thoroughly fine-tuned, it was time to focus on the aesthetics. You’ve got to look good while you’re going fast, so we went all-out with the blingy accessories. For style and function, we added the Acerbis Oversized 3.2 Gallon Tank in Natural. 3.2 gallons is the standard size for desert racing, and the natural color gave our bike a nice accent.
For plastics and graphics, we put together an Acerbis full plastic kit in red and black with a full-custom set of Attack Graphics in their new matte finish on top. To go along with that, we powder coated the frame, triple clamps, swingarm, and sub frame. The black finish fit in nicely with our plastics and graphics, and really brought the color scheme full circle. Some anodized components were the final accessories to get installed, serving as an easy and cheap way to completely customize our bike and give it a little more personality.
The Wrap-Up
By the end, our bike was everything we hoped it would be – reliable, competitive, and super fresh. We had a blast building on our CRF450R, but it’s been even more fun ripping it through rides and races. If you have an older four-stroke, or are just interested in what it takes to do this type of build, be sure to check out the Roached2Racing series to get an in-depth look at how we did it!
Tell Us What You Think
Parts Available at Rocky Mountain ATV/MC
Tusk Competition Clutch Kit with Heavy Duty Springs
Wrench Rabbit Engine Rebuild Kit
FMF Q4 S/A Silencer
FMF Power Bomb Header Pipe
Hinson Billetproof Clutch Cover Black
Hinson Momentum Clutch Basket w/ Cushions
Tusk 4-Stroke Oil Change Kit Pro-Honda HP4M Synthetic Blend 10W-40
Tusk First Line Air Filter
Tusk Carburetor Rebuild Kit
Tusk Fuel Mixture Screw
Tusk Radiator Hose Kit Red
Acerbis Skid Plate
Tusk Impact Universal Linkage Guard
Tusk Billet Rear Disc Brake Guard
Tusk High Pressure Radiator Cap with Temperature Gauge 1.8 Bar
Works Connection Aluminum Radiator Braces
Tusk D-Flex Pro Handguards
Tusk Impact Rim - Front
Tusk Impact Rim - Rear
Tusk Motorcycle Spoke Kit - Front
Tusk Motorcycle Spoke Kit - Rear
Tusk Impact Motorcycle Hub - Front
Tusk Impact Motorcycle Hub - Rear
Tusk Aluminum Front Wheel Spacers Kit
Tusk Aluminum Rear Wheel Spacers Kit
Tusk Motorcycle Rim Lock
Pivot Works Swing Arm Bearing Kit
Pivot Works Steering Stem Bearing Kit
Pivot Works Shock Bearing Kit
Pivot Works Linkage Rebuild Kit
Primary Drive Sprocket Bolt and Nut Kit
Primary Drive Alloy Kit & Gold X-Ring Chain Rear Sprocket
Primary Drive Rear Chain Guide
Primary Drive Chain Roller
Acerbis Chain Slider
WPS Rim Strip
Bridgestone Ultra Heavy Duty Motorcycle Tube
Bridgestone Battlecross X30 Intermediate Terrain Tire
Tusk Brake Rotor Bolt Kit
Tusk Aluminum Brake Pedal Red Tip
Tusk Brake Pad - Sintered Metal
Tusk Brake Pad - Sintered Metal
Tusk Oversized Floating Typhoon Brake Rotor Kit, Front
Tusk Stainless Steel Typhoon Brake Rotor, Rear
Tusk Front Motorcycle Steel Braided Brake Line Standard Length
Tusk Rear Motorcycle Steel Braided Brake Line Standard Length
NGK Iridium Sparkplug
Tusk Billet Start/Kill Switch
Tusk Multi-Function Tach/Hour Meter
Tusk Nyloc Axle Nut
Tusk Rear Brake Clevis
Tusk Aluminum Oil Filter Cover
Tusk Billet Bling Kit
Tusk Billet Aluminum Steering Stem Nut
Acerbis Replica Plastic Kit
Acerbis Lower Fork Protectors White
Acerbis Air Box Mud Flap Black/td>
Attack Graphics Factory Seat Cover
Attack Graphics Custom Blitz Complete Bike Graphics Kit
Acerbis Fuel Tank 3.2 Gallon
Acerbis Front Number Plate
Pivot Works Fork Kit
Bel-Ray High Performance Fork Oil
Pivot Works Shock Rebuild Kit
Bel-Ray HVI Racing Shock Fluid
Tusk Brake Lever
Tusk Clutch Lever
Tusk Folding Shift Lever
Tusk Kick Starter
Tusk Billet Race Foot Pegs
Tusk Universal Rubber Mounted Handlebar Clamp Kit
Tusk Throttle Cable
Odi V2 Half Waffle MX Lock-On Grips
ODI CFT Podium Handlebars Country Boy Bend
ODI Grip Donuts
Magura Hydraulic Clutch
Buyer Guides //
Instagram Feed