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.
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.
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.
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.
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.
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.
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.
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.
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.
It has the most neutral-handling chassis, the best ergonomics, competitive top-end power, and a silky smooth clutch pull.
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.
Helmet: Arai VX-Pro4
Goggle: Fox Racing Vue
Jersey: Fox Racing Flexair
Gloves: Fox Racing Flexair
Pant: Fox Racing Flexair
Boots: Fox Racing Instinct