HONDA CRF450R

Honda’s Unicam cylinder heads combine the best of single- and double-overhead-cam designs. Our engineers redesigned the auto decompression hardware, and also moved it from the right side of the cam to the left. The result is less stalling at extreme low RPM (think deep into a turn without downshifting) as well as better rideability. The CRF450R also gets a whole new cylinder head. Its biggest feature: an oval-shaped centralized exhaust port. Together with the new single-muffler exhaust, it boosts power from 5000 rpm up and increases exhaust efficiency. Lightweight titanium intake valves cut down on reciprocating mass and permit the use of smaller valve springs, reducing 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!