2021 Kawasaki KX250 Review First Ride

[Hugh Janus]

The Kawasaki KX250 is the only 250 four-stroke motocross bike to be completely overhauled for 2021. Team Green’s small-bore motocrosser was due for a major update, having last been fully revamped in 2017. We expected to see this bike released last year, but although the 2020 machine looked identical to the prior trio of KX250s, the engine was much different. For MY21, the KX250 engine has been changed even more, including the addition of electric start. The bike also receives the latest-generation KX450 chassis that debuted back in 2019, which has been highly praised by the Dirt Rider testing team.

Related: 2020 Kawasaki KX250 Dyno Test

Riding the 2021 Kawasaki KX250 at Perris Raceway in Perris, California. (Drew Ruiz/)

Kawasaki invited us to Perris Raceway in Perris, California, to shake down its newest 250F motocross bike and we spent an extra day testing it at Cahuilla Creek MX in Anza, California, to get a better idea of how it performs on a track that has several sandy sections, plenty of hills, and sits at an elevation of approximately 3,500 feet.

2021 Kawasaki KX250 Engine

The KX250 features Kawasaki’s latest-generation aluminum perimeter frame. It is very similar to the 2019-2021 KX450’s with the main difference being the shock tower mount. The lack of a kickstarter presents another easily discernible and welcomed update for 2021—electric start. (Drew Ruiz/)

Even though the 2020 KX250 engine had been updated, Kawasaki continued developing it for 2021 to improve its overall power and added the long-awaited electric start feature. In addition to dropping the kickstarter in favor of a magic button, updates were made to the cylinder head, camshafts, valve springs, piston, cylinder, crankshaft, and connecting rod. The engine’s peak rpm was also increased to 14,500.

The 2021 KX250′s engine characteristics are very similar to the 2020 package with a little more over-rev because of the increased rev limit. They achieved this higher rpm mainly by adding stiffer valve springs along with new camshaft timing. The power delivery is definitely better if you keep the rpm up. Maintaining the correct gear is also important, meaning second gear will be used in most corners. The engine revs far enough that shifting to third gear is not needed until you have exited the corner. Comparing models, I found that the power of the 2020 bike made me want to shift quickly up to fourth, while with the 2021 machine, I feel that third gear is very useful and fourth only needs to be used on faster straightaways.

The EFI mapping runs right from the get-go. There are three different preprogrammed settings available. These are changed via a coupler located on the right side just by the steering stem. Green is standard, white is aggressive, and black is mellow. This is the same system as what comes on the KX450. I tested all three and found improvements with the white and black couplers. Each had improvements, but they also had some drawbacks. The Kawasaki technicians created a custom map that uses the ignition settings of the white coupler and the fuel mapping of the black coupler, which made for a noticeable improvement in the overall power and was accomplished by increasing the midrange torque, which helped it continue to make power further into the highest of rpm. I wouldn’t say it was huge, but it helped with mid rpm torque and seemed to make the power even longer into the upper rpm range.

Putting a smaller-displacement engine in the proven KX450 frame is a recipe for success. The KX250 has a good balance of cornering ability and straight-line stability, and it doesn’t feel long or short in the wheelbase department either. (Drew Ruiz/)

To do this custom mapping on your own, you would need to buy the accessory KX FI Calibration Kit, which retails for $699.95. It can be found on the Kawasaki website and ordered through your local dealer. This is an added expense, but if you are serious enough about your racing, you are probably already planning on getting your suspension revalved and purchasing an aftermarket exhaust, race gas, and more. So, it is worth considering adding this tool to your race budget. The plus side is once you have it and come up with a good map, you can map your friend’s KX and maybe they can give you a few dollars to help offset the cost of the tool.

I was slightly between gears on the 2020 model, but again with the higher-revving 2021 engine, I could fill that gap. In most corners, second gear worked well and carried far enough out of the turn that it was not a panic to grab third. Third gear also felt longer and if your riding style is to just run the gear as long as possible, you will most likely not have to shift to fourth on most local or smaller-sized motocross tracks. Fourth still pulled well as long as you let third gear do its job and rode it up into the higher rpm. I never considered using first gear on our intro day at Perris Raceway as most corners were either open or had a fairly hard base.

The hydraulic clutch is a welcome change. This is the same system that is used on the KX450 and it has proven to work well. The clutch assembly is also all-new, using a cone-disc spring in place of a coil-spring system. The clutch friction plates have also been updated with three different materials to help reduce clutch fade from heat. The clutch worked flawlessly. It was easy to modulate and because of the hydraulic system, there was no fade. Shifting under load was reasonably easy with only the smallest amount of clutch lever input.

2021 Kawasaki KX250 Suspension

The KX250 is in its second consecutive year of having KYB suspension and that is a positive thing as the current 48mm coil-spring fork is very good. Both the fork and shock are easy to adjust, meaning the changes are noticeable but not too sensitive. I made only small adjustments to the suspension to help improve the bike’s performance. The balance of the suspension from front to rear is OK and could easily be adjusted with small changes like the shock ride height (sag).

Throughout the day I made small adjustments to the suspension, mostly to improve the bike’s movement under me. I started with the fork, stiffening the compression to nine clicks open and the rebound to 10 clicks out. This helped with a little less diving on corner entry and kept the front down just a little more though the corner.

On the shock, I spent a little more time working on settings. I began with the sag at 104mm and left the adjusters stock. The bike was a little low in the rear, so I began with going in on the low-speed compression. After going in four clicks, I felt the rear was still riding a little low, so I added a turn to the shock spring, bringing the sag up to 101mm. I liked that change and it seemed to put more weight on the front wheel, but it started to be a little more than the fork could handle on bigger landings. I went back out on the low-speed compression to stock to reduce the amount the shock loaded the fork on jump landings and hitting braking bumps approaching corners. The last change I made was to go two clicks in on the shock rebound. This really helped keep the bike squatted coming out of corners, thereby aiding with rear wheel traction and reducing the pitching effect on corner entry.

2021 Kawasaki KX250 Chassis/Handling

New bodywork and a Renthal Fatbar handlebar are a few other changes Kawasaki’s small-bore motocrosser enjoys for MY21. We also appreciate that it comes with Dunlop’s excellent MX3S tires. (Drew Ruiz/)

The new KX250 chassis is based off the same platform as the KX450. For me, at 5-foot-10, the Kawasaki chassis fits me well and I would say this would be true for most riders. The rider triangle is neutral with plenty of room for adjustment. The handlebar can be moved forward or backward and the footpegs have an optional lower position for taller riders or someone looking to try to lower the bike’s center of gravity. The chassis is also narrow—possibly one of the narrowest four-stroke bikes on the market. Sitting on the KX250, I would say it is a little more of a sitting on top of the bike feeling, but not sitting as high as a KTM or Husqvarna.

The KX250’s narrow chassis is a contributing factor to what makes it so easy to maneuver around on. (Drew Ruiz/)

The brakes are also updated on the KX250 for 2021. The front brake system is the same as the KX450 including the 270mm front rotor. That means the bike now comes with the KX’s very distinct, thin front brake lever. The rear brake now has a smaller 240mm rear rotor (down from 250mm on last year’s model). I like the KX250′s brakes. The front brake lever is noticeably thinner than most other brands. It is fairly easy to modulate and offers a medium to firm feel. The rear brake is noticeably improved with the smaller 240mm rotor. I know this does not sound like a big change, but the previous KX rear brake was way too easy to lock up and inadvertently stall the motorcycle.

How Does The 2021 Kawasaki KX250 Ride?

The KX250 engine’s power is improved over last year. Because of its increased rev limit, the powerplant has a little more over-rev than the prior year model. However, the bike still lacks low-end torque and is a bit loud. (Drew Ruiz/)

There were two new 2021 models I was looking forward to riding and the KX250 was one of them (the Honda CRF450R being the other). The reason is that I enjoy riding the KX450 and putting a smaller engine into that same chassis should, theoretically, result in an even smoother, easier to manage bike. The good news is my assumption was correct. In the past, I felt the KX250 was a sneaky good bike. Maybe slightly underrated because the chassis had not been updated since 2017 and there was a bit of a starting issue—namely that it took a few kicks to fire to life—that held it back in the reviews.

In experimenting with Kawasaki’s power couplers, we found the white (aggressive) and black (mellow) options both offered improvements, but they also had some small drawbacks. There is room for improvement with the EFI and ignition mapping, which requires the use of a KX FI Calibration Kit that retails for $699.95. (Drew Ruiz/)

I have always said there is no issue with kickstarting a competition dirt bike, but now that almost every manufacturer offers electric start on its motocross bikes, it seems to result in a deduction in the bike’s rating if it doesn’t have one. It is not because I don’t want to kickstart my bike, but it’s a disadvantage if I stall it mid-race and lose time trying to kickstart it back to life. The engine power is good and similar to the 2020 model. It is improved over last year and I would still describe the powerband as being similar to a KTM 250 SX-F with a touch less power. The gearing seems appropriate and with some EFI tuning, I was able to get the powerband to work quite well in each gear.

The 2021 Kawasaki KX250 is a well-rounded package. Not having any major weaknesses might very well help it move up the rankings in this year’s 250F Motocross Shootout. (Drew Ruiz/)

This new KX250 handles well. Just like the KX450, it has a good balance of cornering ability and straight-line stability. Riding the bike, it doesn’t feel long or short in the wheelbase department. If you need to turn sharply, you can get forward on the bike to knife to the inside and getting back on the chassis is easy if you are entering a sandy section or need more rear wheel traction. With the balanced chassis, you can do front or rear weight transfers with a less-than-exaggerated movement, unlike some bikes that require you to feel like you’re over the front fender or hanging off the rear fender. For me, this means less physical work and decreased fatigue later in a moto.

I liked the 2020 Kawasaki KX250, but knew it was due for a major update. It was no secret that a major overhaul was in the pipeline as the KX450 received this chassis back in 2019. Now we have it on the small-bore KX motocrosser and it’s everything I was hoping for. Just like its larger displacement sibling, the KX250 does everything well. Nothing about it is head and shoulders better than its competition and nothing about it is below the level of its competition either. This principal has worked well for the latest-generation KX450, earning it the top spot in Dirt Rider’s 450 Motocross Shootout the last two years. It’s too early to tell if the Kawasaki KX250 will win Dirt Rider’s 2021 250F Motocross Shootout, but I can say it is certainly in the running for the most improved model of 2021.

Gearbox

Helmet: Arai VX-Pro4

Goggle: 100% Accuri

Jersey: Thor MX Pulse

Gloves: Thor MX Agile Plus

Pants: Thor MX Pulse

Boots: Sidi Crossfire 3 SRS

2021 Kawasaki KX250 Tech Spec

PRICE	$8,299
ENGINE	249cc, DOHC, liquid-cooled, single-cylinder four-stroke
TRANSMISSION/FINAL DRIVE	5-speed/chain
FRAME	Aluminum perimeter
FRONT SUSPENSION	KYB 48mm coil-spring fork adjustable for compression and rebound damping; 12.4-in. travel
REAR SUSPENSION	KYB shock adjustable for spring preload, high-/low-speed compression, and rebound damping; 12.4-in. travel
FRONT BRAKE	Nissin 2-piston caliper, 270mm disc
REAR BRAKE	Nissin 1-piston caliper, 240mm disc
WHEELBASE	58.5 in.
CLAIMED SEAT HEIGHT	37.4 in.
FUEL CAPACITY	1.6 gal.
CLAIMED WEIGHT	237 lb. wet
AVAILABLE	Now
CONTACT	kawasaki.com

Source

[Tym]

On 07/10/2020 at 18:08, Rogelio Fernandez-Rojo said:

I would trade a kidney to be young enough to ride that.

Trouble is they cost more than a kidney.