2019 Kawasaki KX450

Another Level

Words: Broxy Pics: Paul

Unveiled to the NZ public at the Waikato Fieldays, the stands had barely started coming down before we managed to sneak away with one of the most exciting new models for 2019. And Pirini was the perfect spot for a workout…

Kawasaki has declared war with an all-new 450 for 2019. Unashamedly seeking to match – or even surpass – the strong points of rival brands, it has arrived with an electric start, A-Kit forks and, most surprising of all, a hydraulic clutch. But, as we found out during its NZ debut, that is only the beginning.

You just can’t trust the rumours these days, especially when they claim something like a hydraulic clutch on a Japanese bike. So, when I heard that the big Green Machine was sporting the liquid cable, I casually popped down to the Kawasaki stand at the Fieldays. This had to be seen to be believed. Sure enough, there it was. And much more.

I tried the electric start, and it roared into life. The hydraulic clutch was there as claimed, along with those special 49mm forks. Giving the bike a few revs, even the sound was better than last year’s bike. I then embarrassed myself in front of Kawasaki NZ’s Marketing Manager by activating the launch control as I attempted to turn the bike off. Fortunately, he is just as much of a bike geek as I am, so we avoided the awkwardness by getting stuck into a conversation about all the fun details of the new bike.

“See how the front brake hose comes out from behind the master cylinder now? That is because of how Eli Tomac lost his front brake a couple of times in the AMA races last year. Now the hose is protected when the unit gets hit.” Interesting info, and I was blown away at the complete lack of sponginess in the front brake. It was practically rock hard, like the controls of a race car. That feeling continued as I took it onto the pristine track at Pirini Motocross Park.

It was only fair that Kawasaki’s Mike Cotter had the honour of being the first to ride the KX450 (note: no “F” this year!) on NZ soil. If it had sounded good in the marquee at Fieldays, it sounded even better on the track. There is no hint of the harshness that the prior models had, which was good to make up for the muffler’s massive size.

My anticipation was building as we waited, so I satisfied myself with thinking over some of the changes that might have slipped under the radar. It seems that all the manufacturers are moving to the MX3 Dunlop tyre that has proven so popular, with Kawasaki also following suit this year after many years with Bridgestone. With its taller knobs and softer compound, it really is a good choice. Matched with the black rims, they also look the part.

Something that didn’t change was the old-school handlebars from yesteryear. With all of the other updates, I am a little surprised that they didn’t choose a tapered ‘bar so we will see whether it lasts another year. Not because it really needs updating, I only mention it because of how almost everything else was changed.

In another first for a Japanese brand of MX bike, this year you access the air filter from the side, rather than taking the seat off. It still requires removing two bolts but definitely looks more user-friendly. The best part is how you are less likely to drop dirt into the airbox as you remove it. Getting your hand in there to put it back on is also easier thanks to a flatter design of the air filter cage, giving hints to the changes to its power plant that help give it over three more horsepower than last year’s bike.

Motor Mods

So how have Kawasaki Heavy Industries increased the power so much? It begins with a better throttle response thanks to reversing the direction the intake flap moves. The air then moves through a larger throttle body, up to 44mm diameter compared to last year’s 43mm unit. Even the injectors got work, pumping out a finer spray of fuel to help it mix with the air and explode that much more cleanly. They also pump out 20% more fuel than before. These things are good, but the real magic comes next.

Because they were making an all-new frame, they were able to move the shock across by 5mm. This gave room to move the throttle body higher, helping the air and fuel enter the cylinder from a more direct angle, now at 20 degrees from flat instead of 10 degrees. Using technology from their utterly dominant World Superbike team, saw another big change, with the move to finger followers to activate the cams, increasing the rev ceiling while also saves room. Most importantly, these changes meant they were able to make some massive modifications to those heavy hitters under the head cover.

The intake valves grew from 36mm to a much bigger 40mm in diameter, while the exhaust valves grew from 31mm to 33mm. They also now have more lift, from 9.8mm to 11mm on the intake and from 9mm to 9.5 on the exhaust side. Despite all of these larger valves, the finger followers mean that these components are still lighter than before, helping the bike to rev freely.

The header pipe has also grown in length to help with low-end power, shown by how it now drops downward before going back up and out the back. However, the most important change of all is the big M.A.C. – an acronym I made up for More Aggressive Cams. Opening and shutting the holes quicker is a classic way of increasing horsepower in any sports engine, also allowing the motor to continue making power higher in the rev range.

First Impressions

Finally, it was my turn to ride. I’d probably only been waiting fifteen minutes, but you know how anticipation works. As I felt the bike out, my initial thought that the gear lever looked too low was proven right, but I put up with it for the sake of trying out the new toy first.

Recent rain had turned the Pirini soil rather soft, knowledge that made the power even more impressive. Kawasaki’s 450 has always been known for strong power, but this was on another level. The thing that impressed me first was how it would keep pulling way up high in the rev range. I could hardly find the point where it signed off, and only touched the actual rev limiter briefly a couple of times even though I was trying hard to find it.

Probably the best thing was how the extra horsepower hadn’t made it any harder to ride – in fact, it was quite the opposite. On the one hand, the added pull in the higher revs meant I could avoid shifting up as often. Even better was how the power didn’t feel too snappy. Perhaps it was just the softer conditions that we had at Pirini that day. While the power was instant and substantial the moment you turned the throttle, it wasn’t arm–pump inducing. This is especially important when you first turn the throttle through a rut. It didn’t surge, but came on gently, making it easier to stay in the rut.

Rhys Carter had his turn soon after me and found the power didn’t have the snap that he wanted. Keep in mind that he is in full race mode right now, fit and fast at the halfway point of his Australian MX Championship campaign. Anyway, it wasn’t long before he wanted to try the more aggressive mapping coupler that comes with the bike.

As usual, the green is standard, with white being leaner and meaner, the black richer and more mellow. A nice change for 2019 is how you can now change the couplers while the bike is running, not that you really need to know that it has the electric start button. Anyway, he went with the white coupler and afterwards said it was definitely closer to what he wanted. Kawasaki does give the option of customising your maps with the optional accessory they call the KX FI Calibration Controller for those who want more options, although I think even Rhys would have found the white coupler to be plenty aggressive on a more grippy track. He was still able to make very smooth and consistent ruts around the turns.

We also tried the black coupler, and what impressed me was how it didn’t take away from the top end power, aside from possibly mellowing some of the snap. I’m pretty sure that I would prefer this coupler at most venues in my current state of bike fitness, which is definitely on the low side.

More Than The Motor

All of this is neglecting to mention the weirdest thing about the whole bike, being how unlike a traditional Kawasaki it was to sit on. With the new head configuration, they were able to position the fuel tank with a lower profile fuel pump helping them run a much flatter seat. Instead of feeling like you are sitting inside the bike, you definitely feel more as though you are sitting on top of it. Strangely, it did feel like the seat height had raised. We put it down to the fact that the suspension was brand new and not bedded in yet, although it turns out that the official figures do have it at 5mm higher than last year’s model.

The actual ergonomics are very smooth. Most noticeable is a complete lack of pudginess in the frame width. A few years ago, the KX felt the porkiest of all the 450s, but could now be the skinniest. Following in the footsteps of the KX250F, it feels lighter just because it is narrow.

As for how the bike handles, despite all the changes to the bike’s frame, it still has the stable feel that it is known for. Rhys did choose to drop the forks 2mm in the clamps to help it steer, feeling that it helped him get around the corner without having to force it.

Without going into too many specifics on what they changed on the frame, they did beef up the steering head and now use the engine as a stressed member. The swingarm has also changed in a few ways, noticeable by how the weld is now almost hidden by the frame. Up front is a larger axle shaft, now up to 22mm in diameter from 20mm. This is at the recommendation of the Factory team, showing the passion that these designers have to make this bike all it can be.

Easiest to see, and looking rather cool, are wider frame rails sporting quite a sleek look. Kawasaki claims that these changes are made to increase traction and help the rear tyre drive the bike forward rather than making it squat. Which leads us to the suspension side of things that you have been waiting to see.

Top Shelf

Those A-Kit forks really are nice. They seem to eliminate any feeling of harshness, to the point where they feel even softer than they are. Yes, you can bottom them out, but even that is not a harsh feeling. We did agree that it paid to make them five clicks or so firmer in both compression and rebound dampening, but otherwise, we just enjoyed how smooth they are. Breaking them down, the internal components are basically what the Factory teams use, the larger dampening pistons being the main thing that helps minimize harshness. Those special coatings also help, both in keeping the action smooth and helping it look great.

It was a good thing that the developers had the goal of helping the bike avoid squatting because there was a wallowy feeling through the faster whooped out sections. To help control this we also made the low-speed compression a little firmer, adjusting the rebound to suit. We opted to avoid changing the bike sag for this test, finding that with our little tweaks the bike was working well.

The only qualm was an interesting one because it actually had something to do with the hydraulic clutch. I mentioned earlier how we needed to lift the gear lever. Rhys chose to do that even before he rode the bike, and I am glad it was him doing the work because it took him quite a while. The bolt is in an awkward place, and even after lifting it up a notch it wasn’t really enough, but he couldn’t lift it another notch or the lever would have been knocking on the actuation point of the hydraulic clutch when shifting up a gear.

Probably the best way around this is to make use of the great feature Kawasaki has of being able to lower the position of the footpegs. I assume we would have to be careful to not go too far in case it also moved the footpegs back too far for our size 10-11 feet, but as it was, we got used to it. The gears were not the smoothest to shift either, something that could well improve once new oil was put in it.

So, as we started this story by talking about the hydraulic clutch and those brakes – it would only be fitting to finish with them as well. There was definitely a bling factor to the clutch, increased by how smooth it was. I wouldn’t really say it had a lighter pull than a cable, but it would not be susceptible to fading, which is very nice. Best of all, it still had the most progressive feel that I have felt in any hydraulic clutch before. This is a Nissin unit, and they seem to have mastered the art of combining the best of both worlds. It feels like it has free play like a cable, then comes on really smoothly with plenty of leeway. Not that we needed the clutch much, as the new engine provided for most of our needs. These things will no doubt help it to last longer, especially in muddy conditions.

The front brake was also a thing of beauty. I didn’t really notice it until trying to do some nose wheelies down a grassy slope. The rear wheel came off the ground with barely any effort at all, which would have been a little scary had the front brake not been so easy to modulate. I suddenly had much more confidence in attacking the braking points of turns, knowing I could stop quickly with less effort and more safety should the front wheel decide to lock up.

In all of this, Kawasaki has taken the best components of what it could see in its main competitors and aimed to match them. That would be enough of a statement by itself, but they had to go one better. The rear brake on the KX450 sports a 250mm disc, making it the largest of all brands. Again, it is not something you will probably notice until you really need it, except to know that Kawasaki is out to make a statement.

2019 Kawasaki KX450 Specs

Price – $14,695

Overall length – 2185mm

Overall width – 830mm

Overall height – 1275mm

Wheelbase – 1485mm

Ground clearance – 340mm

Seat height – 955mm

Curb mass – 110kg

Fuel tank capacity: – 6.2 litres

Engine Type – 4-stroke, DOHC, water-cooled, single-cylinder

Bore x Stroke – 96.0 x 62.1mm

Displacement – 449cc

Compression ratio – 12.5:1

Fuel Supply – Fuel injection (ø44 x 1)

Starting system – Electric

Ignition system – Digital DC-CDI

Frame Type – Tubular, semi-double cradle

Suspension –   Front: 49mm inverted telescopic fork with adjustable compression and rebound damping

Rear – New Uni-Trak with adjustable dual-range (high/low-speed) compression damping, adjustable rebound damping and adjustable preload

Wheel travel – Front 305mm/ Rear 307mm

Rake/Trail – 27.6º/122 mm

Tyre: Front/Rear – 80/100-21 51M / 120/80-19 63M

Brakes Front – Single semi-floating ø270 mm petal disc dual-piston

Brake Rear – Single ø250 mm petal disc, single-piston

Changes At A Glance

All new engine produces 3.4hp over the 2018 model and has a flatter torque curve.

Electric start with Lithium-Ion battery.

Hydraulic clutch.

New frame uses the engine as a stressed member.

Return to spring fork, now 49mm.

Dunlop Geomax MX3SF tyres.

Larger front axle.

Bigger brakes (270mm front, 250mm rear).

New slimmer ergonomics.

Maps can be changed with the engine running.

Revised rear shock linkage ratio.

New graphics.

More Performance

The new engine boasts an increase in peak power of approximately 3.4hp while a flatter torque curve makes it easier to get on the gas. Finger-follower valve actuation (a valve train designed by Kawasaki’s MotoGP & World Superbike engineers) enables larger-diameter valves and more aggressive cams. Downdraft-style intake and reduced friction loss (care of new plain bearings for the connecting rod big-end) further contribute to the power gains.