CRF450R

Honda’s Unicam cylinder heads combine the best of single- and double-overhead-cam designs. With redesigned auto decompression hardware and the cam positioned on the left side, the result is less stalling at very low RPM (think deep into a turn without downshifting) as well as better rideability. The CRF450R cylinder head’s biggest feature is its oval-shaped centralized exhaust port. Together with the single-muffler exhaust, it boosts power from 5000rpm up and increases exhaust efficiency. Lightweight titanium intake valves cut down on reciprocating mass and combined with smaller valve springs, reduce overall engine height.

Notice that button on the handlebar by the clutch perch? The CRF450R gets our Honda Selectable Torque Control (HSTC). You can choose from one of three settings to perfectly dial your bike in depending on how much traction is available.

The CRF450R features a downdraft intake tract and FI body to help increase both power and fuel-metering precision. It’s part of the reason the CRF450R offers such explosive power and massive torque, especially out of the starting gate and in the critical first 30metres of the race to the first turn. We’ve changed the angle where the fuel-injector fits into the CRF450R’s intake tract. By steepening the angle from 30 to 60 degrees, the injector now sprays fuel all the way back to the throttle butterfly. The engine gets a cooler, denser fuel charge for more power and better torque. It’s little details like this that put the CRF450R up front.

Out with the old cable-actuated clutch and in with the first hydraulically actuated clutch we’ve offered outside of our works bikes. Made by Nissin, it’s the same design as in our Grand Prix MX machines and performs better than third-party conversions. You get a clutch-lever pull that’s lighter at its peak, even though it’s paired with a new, stronger 8-plate clutch. Plus, you’ll never have to worry about making a clutch-cable adjustment, even during the longest events. We’ve also made improvements to the clutch assembly itself. Say good-bye to clutch fade—we’ve upped the number of clutch plates from seven to eight, to improve durability and hook up. That means 85 percent less slip at peak horsepower and 27 percent more total torque transmission through the clutch pack.

We’re talking about a special ECU program here: push the button to select the mode, hold the throttle open, release the clutch, and the CRF450R will do the rest, launching you into the first turn with a big advantage. It turns your bike into a holeshot-seeking machine!

This simple handlebar-mounted button lets you dial in engine power delivery character with a push of your thumb. Choose between Standard, Smooth and Aggressive, depending on track conditions. Also, check out the controls. We’ve made them lighter and more intuitive. Controls used to be your bike’s shifter, clutch, and brakes. Now you have things like launch assist, selectable power modes, and more. We believe they should be easy to use, and we’ve just made them easier.

Brakes are for more than just stopping: they help you set up the bike in turns and jumps. Which is why we pay so much attention to detail like brake pads. They’re designed to last longer and give you more stopping power—a real win/win to help you win. The CRF450R’s large front-brake disc measures a whopping 260mm. You get great brake feel and a pattern that cuts down on weight. Front and rear brake-disc guards are part of the package too.

Kickstarting? Maybe if you’re riding in the vintage class, but not here. By ditching the kick-starter entirely, our engineers can make the CRF450R lighter. Electric starters and lithium-ion batteries are so light now and so good that putting them on a bike like this is a win/win combination. And winning is what a CRF450R is all about.

We’ve increased the front suspension’s stroke by 5mm, for better handling and rider comfort. Also, we redesigned the axle holding fixtures at the bottom of each fork leg—that increases rigidity, and enhances steering precision and suspension performance.

The 49mm Showa fork features a conventional spring design that helps increase the CRF450R’s front-suspension precision, handling and feel. The spring rate provides better bottoming resistance and improved handling.

Great handling starts with a superior frame and we’ve made some big changes to our CRF450R’s chassis. First, it’s lighter—about 1 kilogram lighter. By making the frame’s main spars narrower, we saved weight, but more importantly, we made the chassis more responsive by reducing lateral rigidity 20 percent. The result is a bike that gets into, around, and out of corners faster. Body work is slimmer, with less and we reduced the total number of pieces and fasteners needed to remove the body panels so maintenance just got easier too. We totally redesigned the rear subframe to make it nearly half a kilo lighter and along the way simplified its construction too.

The narrow swingarm, designed in conjunction with the frame, uses narrow main members (just like the frame uses narrow main spars), to match the swingarm’s lateral rigidity to the rest of the chassis. The titanium fuel tank is also light and strong, while freeing up more space and helping to centralize fuel mass.

Three key features here: The battery box sits low, for an improved centre of gravity. Second, it’s easy to service. Third, it’s water-tight, so there's nothing to worry about when racing in wet conditions.

The muffler’s construction is a pressed-alloy design, it is lighter and offers better rider ergonomics. The routing closer to the centre of the bike also makes it lighter, and helps improve weight distribution. The air filter and airbox shape help deliver more torque. You can access the airbox through the left number plate. And because the filter has no rubber gasket where it interfaces with the intake boot, cleaning and servicing the filter is faster and less messy than ever.

The CRF450R is a perfectly matched package. The upper and lower triple clamps are designed to match the frame and swingarm lateral stiffness and the fork legs axle fixture. Working in concert, they help improve and balance total rigidity, responsiveness and turning performance.

The CRF450R’s rear shock is optimised to match the frame, and the settings work in conjunction with the frame. The shock’s valving resets faster for better response. In addition, steel spring is very light, cutting weight without cutting performance.