Best Motocross Bike 4th Place—2021 Kawasaki KX250

Hugh Janus · December 18, 2020

It seems as though an all-new Kawasaki KX250 has been in the works for a while, but it’s finally here in 2021. Perhaps that wait was prolonged by how much we’ve enjoyed riding and testing the KX450 since it received a complete revamp in 2019. We figured the KX250 would enjoy those same updates—namely the chassis—and sure enough it did, though a year later than we originally anticipated.

“Overall, the Kawasaki KX250 offers a great package with its linear power delivery, simple suspension setup, and being one of the most agile and nimble bikes in the class. Although, its EFI mapping changes should be able to be done on the fly, which is not the case with the couplers.” —Michael Wicker (Jeff Allen/)

The all-new KX250 retains several of the same qualities we praise the KX450 for in the handling department, but some of the engine’s characteristics along with the power delivery still leave a bit to be desired. Also, the suspension is still on the firm side for the average 250F rider, and even those who are on the heavier or faster side of the spectrum for that matter. Fourth place doesn’t warrant how great of a bike the 2021 KX250 is because it’s the most improved 250 four-stroke motocross bike for this year and is nipping at the heels of the top three finishers in this comparison test.

Related: 2021 Kawasaki KX250X Review First Ride

The Kawasaki KX250 is the most significantly updated 250 four-stroke motocross bike of 2021. It is improved in many ways over its predecessor, but misses the mark in a few key areas in stock trim. (Jeff Allen/)

2021 Kawasaki KX250 Engine

Runs on the Dirt Rider dyno were in order for the KX250 and the four other bikes before the comparison test got underway. After mounting a Dunlop D404 street tire on the rear wheel, we conducted a number of pulls on the green machine and documented 39.6 hp at 13,200 rpm and 18.4 pound-feet of torque at 9,400 rpm. With those figures, the Kawasaki ranks third in peak horsepower and fourth in peak torque.

Producing 39.6 hp at 13,200 rpm and 18.4 pound-feet of torque at 9,400 rpm on the Dirt Rider dyno, the KX250 ranks third in peak horsepower and fourth in peak torque. (Michael Gilbert/)

The KX250 produces slightly more horsepower than the Yamaha YZ250F from 4,000 to 5,500 rpm, but makes less than all of the other bikes from 5,500 to 8,800 rpm. It passes the YZ250F back at 8,800 rpm, matches it from 10,200 to 10,700 rpm, then surpasses it from that point until 12,400 rpm. The green machine rises above the CRF250R at 12,200 rpm until hitting its 14,500 rpm rev limiter. The KX250 is unable to match the KTM 250 SX-F and Husqvarna FC 250 at any point along the horsepower curve from 5,000 rpm all the way to peak.

Related: Best Motocross Bike Winner—2021 Kawasaki KX450

As far as torque, the Kawasaki makes the least of all the bikes from 5,500 to 8,800 rpm, then passes the YZ250F at that mark and matches it at various points along the torque curve including from 10,000 to 10,600 rpm and 12,000 to 12,600 rpm. The KX250 makes less torque than the 250 SX-F and FC 250 from 5,000 rpm until they each hit their respective rev limiters and produces just a touch more than the CRF250R from 12,700 to 14,000 rpm.

“The Kawasaki offers a good, broad power with decent torque and over-rev. However, it seems to struggle a little with recovery when missing a downshift—mostly when you should have been in second gear and got caught in third.” —Allan Brown (Jeff Allen/)

Possessing a fairly broad power delivery, the KX250 can carry a gear well into the rpm range and works best when ridden that way. It has more bottom-end power than the CRF250R, but noticeably less than the YZ250F and not quite as much as the 250 SX-F or FC 250 either. Although the Kawasaki has a quick, free-revving nature, it lacks some torque feel throughout the rpm range compared to the top three finishers in this shootout as well. Therefore, if you miss a downshift, it takes a moment for the bike to recover and get back into the meat of the power.

For all of those reasons, the KX250 still has a mostly intermediate- to pro-level engine package in that it requires an aggressive throttle hand and a finger on the clutch in case the rider loses momentum or is in the wrong gear and needs to coax it back into the upper echelons of the rpm range. Thankfully, the KX’s new Nissin hydraulic clutch offers a smooth, nearly effortless pull that makes it almost enticing to use. The green machine rivals the YZ250F for being the loudest bike in the class and is the raspiest sounding as well.

2021 Kawasaki KX250 Suspension

“The suspension on the KX250 took the longest for me to find the right setting, and even then, it still felt very stiff over small- to medium-sized chatter bumps and deceleration bumps.” —Michael Gilbert (Jeff Allen/)

Kawasaki spec’d the KX250 with a KYB 48mm coil-spring fork and KYB shock last year, which we felt were too stiff. Those same components return on the 2021 model, but with a one-rate-softer fork spring setting of 4.9 Nm and the same shock spring rate of 54 Nm. Although the softer fork springs help provide more comfort compared to last year’s model, the KX250′s suspension setup is still the stiffest of the bikes gathered here. Its excessive firmness is mostly noticeable on braking bumps—namely those of the small- to medium-size variety—and becomes increasingly apparent as the track gets rougher.

On smoother, jumpier tracks, the KX250′s suspension setup is acceptable, but on a rough and demanding track like Glen Helen, it provides the least rider comfort and the most feedback on acceleration chop and braking bumps, especially those that are square-edged. The KX250′s firm suspension setting matches its engine package in that it works best in the hands of an intermediate- to pro-level rider, but even those more skilled pilots may find themselves going out on the compression and rebound clickers at both ends in search of more comfort and movement from the KYB components, especially if they weigh under 160 pounds.

To further indicate how firm the KX250′s stock suspension setup is, even our heaviest test rider of 175 pounds and Vet Expert in skill level went out five clicks on the fork compression, three clicks out on the fork rebound, five out on the shock’s low-speed compression, a half-turn out on the shock’s high-speed compression, and three clicks out on the shock rebound before he found the comfort he was looking for.

2021 Kawasaki KX250 Chassis/Handling

Kawasaki added electric start to the KX250 for 2021. While that feature is certainly a welcomed addition, it is a major contributing factor to the bike gaining 5 pounds over the prior year model as it now weighs 238 pounds, making it the heaviest motorcycle in this comparison test. (Jeff Allen/)

Equipped with a frame that is based off the KX450′s and sharing the same swingarm as its larger-displacement counterpart, the KX250 is one of the best-handling machines in the class and features the best overall ergonomics. It offers the most neutral handling characteristics between cornering capability and straight-line stability, and is the narrowest from the radiator shrouds all the way back to the number plates, which make it the easiest bike to move around on. It also possesses a nimble feel despite being the heaviest motorcycle in this comparison test at 238 pounds.

“Because I very much enjoy riding the Kawasaki KX450, I figured I would like the KX250 even more being that I am on the lighter side of the weight spectrum. However, that assumption proved to be incorrect. As it is on the 450, the smaller-displacement KX’s chassis is remarkable in the way it handles neutrally and offers the best ergonomics, but I feel its potential is hidden beneath a stiff, overly sprung suspension setup for the average 250F rider.” —Andrew Oldar (Jeff Allen/)

The KX250 has somewhat of a stink bug stance, which is magnified by the recommended shock sag setting being a relatively high 102mm. To combat this, some test riders increased the sag and went a half-turn out on the high-speed compression. Contributing to the KX250′s class-leading ergonomics package is its neutral rider position, near-perfect rider triangle, flat seat, and sit-on feel.

Why the 2021 Kawasaki KX250 Should Have Won

It has the most neutral-handling chassis, the best ergonomics, competitive top-end power, and a silky smooth clutch pull.

“Initially, I could not keep the KX250 under control. It felt very bouncy and stiff; the bike would skip across bumps and wouldn’t go through them. I went two clicks out on the rebound front and rear, and it was a lot more plush and planted. On the plus side, the bike is narrow, very nimble, and plants nicely in ruts.” —Tanner Basso (Jeff Allen/)

Why the 2021 Kawasaki KX250 Didn’t Win

The engine lacks a little bit of low-end power and some torque feel, and the suspension is stiff and a bit harsh in stock trim, especially for those who are on the lighter side and novice level in ability. Also, we would like to see the KX250 feature a handlebar-mounted engine map select button instead of EFI couplers.

Gearbox

Helmet: Arai VX-Pro4

Goggle: Fox Racing Vue

Jersey: Fox Racing Flexair

Gloves: Fox Racing Flexair

Pant: Fox Racing Flexair

Boots: Fox Racing Instinct

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