Honda CRF450RX vs Yamaha YZ450FX

When two of the biggest Japanese players entered into the big bore cross country arena, it produced arguably two of the best machines in the class. But which tops the list? We headed to the tracks and trails of Pirini to see if we could find out…

Words: Paul Pics: Paul

It’s not rocket science. Take your MX1 four-stroke machine, swap the rear wheel out for an 18-incher, add an electric leg, soften the suspension and don’t worry too much about lights or any other electric gubbins. You’d think it would be a no brainer, especially as the Euros have been doing so well with their XC varieties. But no, it’s taken years for the Japanese to come up with the same solution, although when they finally added 450 XCs to their ranges, the bikes they produced proved to be stunning examples of the sorts of machines we love here in Godzone.

The Contenders

Having a YZ450FX and a Honda CRF450RX at the same time meant there was no choice but to put the two head-to-head. It would have been great to have had a KTM along at the same time, but with the 450XC producing so much mumbo, it appears that everyone knows it’s too much and go for the 350XC instead. It’s a sensible choice as the 350 is a sweet machine. But we’re here to test 450s, so the FX and RX were going to be put head-to-head.

The FX has been around since 2016 when it was launched officially in Queenstown. We sent Chris to sample the fun and he came back saying The more hours I put into the 450FX, the more comfortable I felt on it”. Which makes it a real shame that we haven’t had the opportunity to sample the FX again since, so having one along for this test was going to be fun.

The Yamaha is based around the YZ450F motocrosser, a bike which breaks from the norm of the rest of the moto scene. A backwards facing engine allows a more direct route for the air to flow, the petrol tank is located under the seat, and the airbox is up where the tank used to be. It’s innovative, different and really seems to work, with the blue bike posting some of the bigger horsepower figures in the segment.

Meanwhile, the Honda is a bit more traditional, well, apart from the twin shooters out the back. Yep, the CRF450RX has retained the twin exhausts of the MX1 machine and it looks awesome for them. Powering the CRF is Honda’s trusty Unicam powerplant which, like the Yamaha, has gained an electric leg but unlike the Yamaha has also retained the manual version too. The FX relies on the button and having a healthy battery, which tends to make us a bit nervous entering the bush for a longer ride. It doesn’t take much cranking over for the small batteries fitted to these machines to get to the bottom of their reserves, and while having the back-up kick starter might add a fraction of weight but it’s a necessity in our books.

Even though the Honda might look racier to the casual observer due to the twin pipes, jumping on board swaps the tables. The Honda is a little old school in a CRF450X kind of way, and you can almost feel Honda’s stalwart off-road bike creeping in through many assets of the RX. The Renthal handlebars and the riding position are 450X through and through, as is the delivery from the powerplant which has been tuned for bottom-end torque rather than a screaming top-end. The RX feels comfortable and familiar, which couldn’t be farther from the truth with the Yamaha.

Sit aboard the blue machine and the first trait you recognise is the towering saddle. At 965mm from the floor, the FX is just another Yamaha to make your eyes water and you’ve got to think the Yamaha engineers have the longest instep of anyone in the world if they think a saddle almost a metre from the floor is okay. Thankfully, the FX is narrow – I mean seriously skinny! – with the middle of the bike almost disappearing between your legs when you’re standing on the grippy footpegs. It takes a bit of getting used to, but once there, you begin to realise the Yamaha is a supremely flickable machine with the low C of G and skinny ergos making it feel much less than a traditional 450, especially one wearing an electric leg…

Neither bike has got much of a dash to speak of, with the cross country theme keeping unnecessary gizmos to a minimum in order to save weight. Neither have got a headlight either, and the lack of unnecessary extras means they’ve both managed to keep the weight down on these bikes. Despite that, there’s still a price to pay for having an electric start, a sidestand and a slightly bigger tank with the RX tipping the scales at 118kg wet while the MX R-version is a claimed 110.6kg. The Yamaha shows the same sort of gains, with the FX slightly heavier at 119kg wet, while the MX version is 112kg. The only time you really feel the extra kilos is when you’re pulling them out of the trailer, lifting them off the sidestand or picking them up off the floor. Once you’re moving the extra weight disappears, which is especially true with the Yamaha thanks to that slim mid-section. Also helping the featherweight feeling is the lack of electronics mounted to the handlebars, with a clock and headlight seriously noticeable on more trail or enduro machines.

Ripping It Up

With two eagerly anticipated bikes to test, it didn’t take long before Mitch and Tarver were ripping up the tracks and trails trying to get a bead on which was their preferred machine. With the RX actually Mitch’s bike, we got him to revert all the settings back to base, but it was obvious he was still extremely comfortable on the Honda. “Everything is that good nowadays, they all just need fine tuning to get the best set-up. The Yamaha is a good all round bike and has got more than enough power, but it’s not spread enough I reckon. The Honda has torque all the way through the range, and even though it doesn’t do anything drastically better than anything else out there, it’s just consistent all the time and that’s why I like it.”

Tarver and myself were both also immediately enamoured with the red machine. The easy ergos, sit-in feeling, predictable power delivery and the way it just got on with the job in hand was going to be a tough act to follow. The RX is typical Honda, jumping into life as soon as you hit the starter and running faultlessly throughout the day despite some pretty tough riding through the powdery berms of Pirini and also while venturing out into the un-groomed trails where the water ruts were big enough to swallow the unwary. This is where the Honda excelled, with the bottom-end hit giving you the confidence to hit anything knowing the RX will just grunt its way to the top.

And then there’s the switchable mapping, which makes a massive difference between modes and lets you set the RX up how you’d like it for any situation. Okay, you aren’t really flicking modes on the fly as the button needs to be held down for a few seconds, but sitting at the foot of a tricky looking hillclimb that had plenty of ruts and jumps to negotiate, I dropped the Honda out of the aggressive mode in favour for the middle setting. It really works and becomes an invaluable tool when you’ve got it.

With 49mm Showas at the front and Honda’s legendary Pro-Link suspension at the rear, the RX steers sweetly, especially as the frame is borrowed from the MX’er. The RX oozes confidence and you can throw it into a turn, hit a berm or pick a rut with almost telepathic intuition – point the RX where you want to go and you’re there. Getting on the gas isn’t quite as easy, with the Honda still more about grunt than all-out horsepower even when you’ve got it in the aggressive mode, so if you’re the sort of rider who likes to punch off a berm, the Honda takes a little getting used to. Once you’ve got it dialled it’s no drama, it just doesn’t come automatically.

Scrubbing speed is good if not exceptional, with the 260mm front disc which is gripped by a twin-piston caliper needing a good tug to get the Dunlop Geomax AT81s to bite in. Using the rear at the same time gets the power up to acceptable levels, but they aren’t the sharpest stoppers out there. That’s a good or a bad thing depending on how you look at it, with a seriously powerful set of brakes more likely to see you lose the front and crash, or head over the handlebars and crash. It takes serious skill to make the most of top shelf stoppers, so maybe having a set which aren’t razor sharp isn’t a bad idea.

And then there’s the Yamaha, which although not as instantly inspiring as the Honda, grew on the testers as the day went on, especially myself and Tarver. “I expected to like the Honda the most,” said Tarver when we’d finished the test. “But after a day of riding, the Yamaha really took my fancy. I felt safer and more comfortable on the Honda and for trail riding, I’d take the RX. But I really enjoyed the thrill of riding the Yamaha, with the suspension especially good at soaking up big impacts. I’m not a fan of the old school handlebars and cockpit of the red machine, with the Yamaha looking much more modern. And the Honda sounds better with the bark from the twin pipes where all you get from the FX is the sound of the airbox. But I imagine with a bit of set-up from someone like Paul Whibley, the FX would be incredible on rides like Desert Storm and Boundary Buster. I reckon it would be incredible!”

When you first get on the FX (and any of the new-breed Yamaha 450s), it feels distinctly different to anything else you’ve been used to. The engine configuration, lack of petrol tank up front and, once you’re going, the noise from the airbox that sounds like it wants to suck your crown jewels into the motor all add up to making a bike that’s different from the norm. Initially, that’s a bad thing and you can’t ride as quickly and confidently straight out of the box as you would with, say, the Honda or other equivalent machines. But then you start to gel with the Yamaha, and we all started to like it more and more.

There’s no denying, the FX is the more focused machine and therefore a better bet for the faster or more advanced rider. The engine is breath-taking, with an instant hit of power as you open the throttle which is completely different to the delivery from the Honda. Where the RX encourages you to hook another cog higher and use the torque to make progress, the FX wants you to grab it by the throat and wring its neck, with the best delivery coming in the mid-to-top of the rev range. Don’t get me wrong, you don’t need to bounce it off the limiter everywhere, and if you try this you’ll discover the Yamaha simply makes more noise but doesn’t really reward with more forward motion. No, the FX loves that upper-middle area of the rev range and feels ballistic when you’re there. That means the open trails of Pirini were a hooting, hollering laugh on the FX, with sand being roosted in every direction as the Yamaha blasted along encouraging you to try and keep up with the gears. It’s the most moto-focused out of the two, and you could easily enter a moto on the FX and keep up with the guys on standard Fs.

But that lead me to be a bit cautious in the technical sections, where I felt the Yamaha was more likely to bite should I get it slightly wrong when compared to the Honda. It’s true that the Honda excels in these conditions and the Yamaha requires a different level of skill and control, but keeping a finger on the clutch and an eye on the revs shows that the FX can bounce and leap through technical terrain just as good as the Honda, it just takes a little more concentration. And when you do need to scrub speed, the Yamaha has you covered with a great set of brakes, with the rear especially strong.

Handling too isn’t quite as natural as the RX, with that reverse engine combined with the towering seat height making the Yamaha require slightly more effort to get it to turn in. Once there and the FX will track superbly and the motor is just waiting to be unleashed in a burst of power while the airbox noise makes you feel like you’re riding fast. And if you’re riding the FX there’s no excuse not to be riding fast, as it’s got as much horsepower as you’ll ever need and the 48mm suspension will soak up anything you decide to throw at it. The rear shock wasn’t quite as composed as the Honda, again making the Yamaha feel a little ‘different’ than a ‘normal’ dirt bike, but get into the groove with the FX and there’s not much that’s going to be able to keep up.

Horses For Courses

Despite both bikes being aimed at the same market and both being a development of their brand’s motocross weapons, it’s quite amazing to experience just how different these two bikes are from one another. The fundamental differences in the powerplants are pretty much the reason, with the double overhead cam configuration of the Yamaha inherently more inclined to produce a peakier power delivery, while the Honda’s Unicam is the complete opposite. The fact the Yamaha’s engine is opposite in direction to the Honda is the explanation for the slightly more effort required to turn, but the fact there’s no fuel tank at the front and pretty much nothing between your legs makes for a riding experience that belies the fact you’re on a 450cc machine. The Honda is much more traditional, and the RX experience is almost like riding an X on steroids.

Deciding between the two is a tricky prospect, as it’s as much to do with what style of rider you are and the type of riding you’re doing as anything else. If you’re trail riding and are maybe on your second dirt bike and wanting something that’s going to develop with you as your fitness and skill levels increase, then I’d thoroughly recommend the Honda. It’s easy, comfortable and there are no surprises. The RX gets on with the job in hand and makes you look good in the process. But if you’re more experienced, faster, maybe do a bit of moto but want something with an electric start, especially when you hit the trails, then the Yamaha is a weapon that won’t disappoint. Once you’ve got it set-up for yourself, the FX is devastatingly quick in various terrains and situations, but that means you need to skill, fitness and ability to be able to hold on. You can adjust the power delivery with the optional Power Tuner, but it’s not as easy as the Honda’s system.

Take the engines out of the equation and both the bikes are very similar: aluminium perimeter beam frame, spring forks, no headlight, 18-inch rear wheel, sidestand etc. But it’s the way that both parties have come to the conclusion of making their powerplant which really distinguishes who the prospective rider is likely to be. I for one had a ball riding both as did Tarver and Mitch, and it’s safe to say that whichever you pick, chances are you’re not going to be disappointed.


Yamaha YZ450FX Specifications

Price: $14,499

Engine Type                Liquid-cooled, DOHC 4-stroke, 4 titanium valves

Displacement              449 cc

Bore x Stroke              97 x 60.8mm

Compression Ratio     12.5:1

Ignition                        TCI

Starter System                        Electric/Kick

Fuel Tank Capacity      7.5-litres

Transmission              5-speed

L x W x H                     2165mm X 825mm X 1280mm

Seat Height                 965mm

Wheelbase                  1460mm

Ground Clearance       325mm

Wet Weight                119kg with 7.5-litres of fuel

Frame Type                 Bilateral Beam

Suspension Front        Telescopic fork, 310mm travel

Suspension Rear         Swingarm, link suspension, 317mm travel

Brakes Front               Single disc, 270mm

Brakes Rear                Single disc, 245mm

Tyres Front                  Dunlop Geomax AT81 90/90-21

Tyres Rear                   Dunlop Geomax AT81 120/90-18


Honda CRF450RX Specifications


Price: $14,495

Engine Type                liquid-cooled single-cylinder four-stroke

Displacement              449cc

Bore and Stroke          96mm x 62.1mm

Ignition                        Full transistorised with electronic advance

Compression Ratio     13.5:1

Starter                         Kick and electric start

Transmission              Close-ratio 5-speed

Fuel Capacity              8.5-litres

Dimensions                 2175mm x 827mm x 1274mm

Seat Height                 960mm

Wheelbase                  1477mm

Ground Clearance       328mm

Kerb Weight                118kg

Suspension Front        49mm fully adjustable leading-axle inverted telescopic Showa coil-spring fork; 305mm travel

Suspension Rear         Pro-Link system; fully adjustable Showa single shock; 313mm travel

Brakes Front               Single 260mm disc with twin-piston caliper

Brakes Rear                Single 240mm disc

Tyres Front                  Dunlop Geomax AT81 90/90-21

Tyres Rear                   Dunlop Geomax AT81 120/90-18