Ergonomics
With bikes as powerful as these 450s, an excellent bike/rider interface is critical, and Honda has the key to our hearts. The new chassis is slim but wide enough for comfort. It has a great seat, handlebar bend/brand and footpeg location. All of the bodywork is smooth with nothing to snag or irritate the rider. Honda pays attention to human engineering, and it shows. The KTM has an excellent handlebar with triple clamps that offer four handlebar positions and two fork-offset (18 or 20mm) positions. We left the clamps at the stock 20mm offset, but some riders preferred the bar clamp moved to the rear position on the top clamp. The standing riding position is roomy and great for tall riders and is adjustable enough to appease shorter pilots. The seated position is sufficiently roomy, but the seat doesn't win over many friends. The orange thumper is also the narrowest of the machines.
The Yamaha won less friends than the KTM. We point to the bend of the new aluminum Renthal bar the blue boys chose for part of that conclusion. The bar is too low with more sweep than we like. Some riders also felt the pegs were high. Riders in the mold of Doug Dubach felt right at home; taller riders were always too far back on the bike. The seat made a few more friends than the KTM's, but not many. It wears less padding than its YZ250 sibling, but it does offer a flatter, more-supportive profile than the KTM's perch.
Engine
Honda basically stuck its 2004 powerplant in the fourth-generation 2005 chassis, so you'd think there would be no performance changes; you'd be wrong. The '05 airbox is much more effective, and as a result, the CRF450R responds harder off the bottom than before. The power can be too strong for indiscriminate throttle jockeys. The higher the rider's skill level, the more he liked the CRF's engine. For one thing, it is the only five-speed, so there are slightly more options when it comes to selecting a gear for a certain track situation. You are more likely to find yourself between gears with the four-speed bikes. The Honda has the hit it needs for stadium-type obstacles, but mostly it has very smooth power delivery. Riders who had a complaint singled out a firm clutch pull.
Between the other two engines, our team selected the KTM as their second favorite. The SX has more-noticeable vibes than the two Asian bikes, but it only bothered the picky or the sensitive. The hydraulic clutch works well, too. The power comes on even more smoothly than the Honda's and in a more linear fashion. More throttle equals more power. There is not much in the way of hit, either. Vet and novice riders regarded the orange engine as less tiring, but aggressive riders such as Lewis found they had to use first gear out of tight turns, and then they missed the first-to-second shift more than they were comfortable with. If you are looking for an engine that makes a lot of power without being intimidating, the KTM is your choice.
We can't say the Yamaha is smooth, and it certainly can be intimidating. It is a little soft right off idle then hits hard and pulls hard through the middle. The power tapers off at high rpm, so it gives the impression it is short-lived. It isn't, but the bike isn't happy when you ride it like a YZ250F. We have issues with the power delivery for a number of reasons. It makes life tough for the suspension and puts the handling under a microscope. With less of a wallop from the engine and more-refined ergonomics, the YZ-F would be a lot closer to the CRF.
Braking
All of these bikes have good brakes. The KTM has the largest front disc and the most power, but some testers thought the front sudden and the rear brake pedal hard to find. When we averaged the numbers, though, the KTM enjoyed a slight edge. The CRF also has very powerful brakes, but they are extremely easy to modulate. Unexpected lockup is never a problem on the CRF.