0 2010 Honda CRF450R vs. Yamaha YZ450F

Let’s take a second to reintroduce the players, the 2010 Honda CRF450R and Yamaha YZ450F. Honda extensively revised its proven winner in 2009, headlined by fuel injection, frame and suspension changes. For 2010, Honda focused on minor refinements to the CRF450R rather than making sweeping changes. Why mess with success?
Yamaha, on the other hand, threw itself into an engineering frenzy. The YZ450F was completely updated with a new frame, new suspension, and a radically new engine. Mass centralization was the key, headlined by a new engine with a backwards-facing cylinder, four-valve head, fuel injection, an airbox relocated to behind the steering head and an exhaust system with more twists than a bag of pretzels.

Before we go any further, we need to make clear this isn’t a shootout so much as it is a comparison of the apex predators of the motocross world. Scheduling and weather didn’t allow us to ride the bikes back to back, but our crew did ride them just a week or so apart. We didn’t only take them to one track either; we rode them on groomed motocross tracks, fifth-gear cross-country terrain and tight East Cast singletrack. We even twirled the wrenches to see what it’s like to live with these beasts in the real world, all the while taking a ton of notes from our squadron of six test pilots. Just so you know, those riders ranged from spode to Pro, with weights varying from 140 pounds to 190 and heights from 5’6 to 6’. Once the dust cleared we had an old-fashioned bench racing session, which resulted in yet another mound of hand-scribbled notes.

Yamaha claims the YZ450F weighs 245 wet. Honda claims 235. Reality? They both feel about the same to hoist onto the work stand, but the Yamaha is easier to lift thanks to the open area where the airbox normally resides. On the track the Yamaha feels substantially lighter than the Honda. Evidently all the mass-centralization weird science Yamaha engineers incorporated into the new chassis and engine have paid off.

Kick starting is easy on both bikes when they are cold, with no need for special techniques, black magic or crossing your eyes and holding your tongue a certain way. When the bikes get hot, or end up upside down, or are otherwise crashed, the Honda relights easier. Notice we said ‘easier’ and not easy…it still takes a bunch of hefty kicks and swear words. Under similar…ahem…’purely scientific test conditions’ the Yamaha was even more reluctant to fire up. We’ll get back to this in a minute.

When it comes to engine performance, the ‘raw grunt’ award goes to Big Red. The CRF has an aggressive, muscular powerband from top to bottom. It’s usable but at times intimidating and tiring. Still, it’s nice to have that snap when you need a shot of confidence to clear a big gap or tackle an impossible hill. The Yamaha is a little smoother and easier to ride, with a more pleasant powerband for the average rider. Both bikes have well thought out gear ratios and both shift well, though the clutch pull on the Yamaha takes significantly more effort.

On the track the Honda felt familiar to all of our testers. They praised the action of the rear suspension, but not the forks. The Yamaha suspension was so amazing at both ends one of our testers notes said “best production bike suspension ever.” The Yamaha also had a lighter feel and accurate turning that made it very pleasant to ride. The Honda has the advantage of stability at speed, thanks mainly to the adjustable steering damper.

Once you get further off the track, into the realm of off-road racing, the overall Yamaha handling package puts it solidly ahead. The Yamaha fork and shock, minus some compression clicks, are okay for aggressive singletrack riding. The Honda was handicapped off the track by its fork. Big hits were no problem, but the Honda’s KYB fork did not like stutter bumps, braking bumps and trail junk. The shock on the Honda, however, worked quite well in the woods with minimal adjustments. In snotty first- and second-gear singletrack the Honda feels bigger, heavier and nastier than the more nimble and better-suspended Yamaha.

While we are playing lumberjack, we can say engine-wise the Honda was better in the woods than the Yamaha with stock EFI mapping. It doesn’t stall too easily, has tons of power on command and is blessed with a perfect clutch and transmission. The Yamaha stalled easily, was harder to restart, the clutch was too heavy and first gear was too tall. That drove us nuts, because the overall powerband and handling of the Yamaha were better suited to woods racing than the Honda. That brings us neatly into the next subject. Living with the bikes.

Everyone knows how to tune the Honda. It’s been around a while and there seems to be more aftermarket parts available for it than there are for a small-block Chevy. CRF450Rs get converted into everything from pro Supercross bikes to vet-rider trail bikes every day. The split engine/gearbox oil is a boon to reliability and Honda’s build quality is second to none. The airbox is still a pain to access, but the EFI tuning port is easy to get to if you feel the need to fine tune the settings.

In contrast the Yamaha is a new entity. We found the Yamaha easy to work on, super-easy even. It reminds us of European enduro bikes in that regard, with most items thoughtfully placed out in the open. The airbox location, aside from the excessive number of small fasteners you need to remove in order to access it, is great. This sounds dorky to say, but everyone mentions how the new airbox location makes the bike sound really cool! The cylinder head is easy to access, but oil changes are messier than on the Honda. The white plastic of our test bike looked cobby when it was new and turned nasty in a hurry. The EFI is very easy to tune with the YZ power tuner, which is where we’ll focus our attention in the next blob.

Remember when we said the Yamaha drove us nuts when we left the motocross track and headed for the real world? In an effort to improve things we fiddled with the Power Tuner for hours, learning a whole bunch in the process. When we first whined about it to Yamaha they sent us some off-road EFI specs to try. Those might have worked for Baja, but for tight woods they sure didn’t help. So we got creative, basically fattening up the fuel curve off the bottom and backing off the ignition timing with the goals of improving low-rpm response and smoothing out the transition into the midrange. Eventually we had the bike running so well that no longer did the gearing seem too tall, it rarely stalled and always started easily. These are the mellow EFI settings we liked for off-road racing and general play riding.
YZ450F EFI Settings
Fuel 4000 rpm 6500 rpm 9000 rpm
1/8 +4 +4 -3
3/8 +4 +4 -4
6/8 -3 -4 -4
IGN 4000 rpm 6500 rpm 9000 rpm
1/8 -3 -3 -3
3/8 -3 -3 0
6/8 -3 -3 -3

We went the other way with tuning as well, just to see how hard we could make the YZF pull on our ¼ mile dirt track ‘real-world’ dyno. We ended up being happiest with stock settings, but it’s nice to know how easily the Yamaha can be tuned for different conditions, fuels or modifications.

Bottom line? It depends who you are. The CRF remains an absolute weapon on the motocross track, with its few weak areas easily cured though the aftermarket. It’ll do anything you ask of it, sometimes begrudgingly and needing a little help, but it will do it.

The YZF, however, is an easier bike to own and to live with no matter where you are riding. How can we say this? All our testers wanted to sleep with the YZ450F and none of them would kick the CRF out of bed, but in the end it was only our Pro rider who really liked the Honda. Everyone loved the Yamaha.