2018 Kawasaki KX250F vs. 2018 Suzuki RM-Z250
The 2018 250cc MX Shootout is just around the corner and what better way to put some time on each bike than to compare them in a head-to-head battle? We grabbed two of the first 2018 model 250Fs we received and put them straight into a Showdown after finishing a First Impression of each machine individually.
The Kawasaki KX250F received a few minor updates after undergoing a complete overhaul in 2017. The changes made to the 2018 model include a new throttle body, fuel pump, intake camshaft, and header pipe. Kawasaki also changed the intake duct, shortened the intake funnel, and revised the ECU settings. Suspension changes were made to the front and rear ends of the bike with the Showa Separate Function front Fork (SFF) receiving a softer spring and more preload on the right leg while the left leg has new compression, rebound, and BCV shim settings. The shock changes are similar to those made to the fork including new compression, rebound, and plug-bolt settings.
The Suzuki RM-Z250 is largely unchanged for 2018 with the exception of a few minor cosmetic changes, which include white number plates and blue accents on the seat and radiator shrouds. We took these two bikes to Glen Helen to see how they stacked up on the iconic Southern California track. Here’s what test riders had to say after a full day of testing:
Michael Wicker, Age: 19, 5’9”, 140 lb., Intermediate
From the first time I sat on the Suzuki RM-Z250, I noticed the comfort of the seat and the shape of the bike. It felt very slim and nimble through the chop and braking bumps. The clutch pull felt very stiff, which made shifting a little difficult, and a lot of shifting is required on this bike. The motor was way down on power and very slow on building rpm. I feel if this bike had a lot more bottom-end hit and more overall power, it could be very competitive.
This was the first time I have tried the KYB PSF2 air fork, and I feel it is now my favorite air fork. The setup was very simple, something I rarely see with air forks. I noticed the more aggressive you are with this suspension, the smoother the ride tends to be.
The handling on this bike was amazing. It’s extremely nimble and corners like a dream. The chassis makes it very maneuverable and agile. I liked the brakes as they were powerful but not too touchy or grabby to where you start losing the front or rear of the bike easily. The throttle pull was also nice, but I feel it needs quicker throttle response. Overall the RM-Z250 is solid as far as suspension and handling, but it lacks the power, especially for a 250F.
Overall, I was very impressed with the Kawasaki KX250F. I loved the bar placement as well as its slim feel and seat shape. The clutch and throttle both have a nice light pull. Shifting was also incredibly smooth and I didn’t stall or mis-shift it once the entire day. The fork was very simple to set up, and only small changes were needed to make me feel comfortable on it. Similar to the Suzuki, I noticed the more aggressive you ride the bike, the better the suspension works. The KX250F doesn’t have the plushest of forks, but it worked well for me so long as I rode aggressively. The shock action was very progressive feeling and consistent, which helped it stay nice and straight through the big braking bumps.
The KX250F engine felt very smooth and the top-end power was impressive. The bottom-end wasn't bad, but I feel just a little more snap on there would make this bike very strong overall in the engine department. The gears were spaced pretty well, and keeping the rpm up on this bike was not hard at all. Overall the KX250F has a good engine, but more bottom-end power would make it better.
The handling on the KX250F was good. I could be aggressive coming into the corners and know the bike will work with me. It is easy to lean into the corners and maneuver to different lines with ease. The nimble chassis makes the Kawi feel very flickable, especially in the air. This bike is easily one of the most comfortable 250s I have ridden to date. Overall, the Kawasaki KX250F was fun to ride and very easy to get comfortable on.
Comparing the two bikes was a little tricky in some areas—mainly the suspension and handling. For the suspension, I preferred the KYB PSF2 fork and KYB shock on the RM-Z250. To me, they felt just a little plusher, which I prefer, especially on really rough tracks. I made similar adjustments to both bikes. I mainly softened the compression and rebound and both were easy to find the setting I liked.
As for the engines, the Kawasaki KX250F was unbeatable. The power delivery was a lot stronger than the Suzuki, and for a 250, I like a lot more of an explosive type of power, especially on the bottom-end. I did not care for the shifting on the Suzuki and feel it could be a lot smoother. The Kawasaki on the other hand shifted incredibly smoothly. The way the KX250F builds power was a lot better for me and it suited my style of riding better.
The handling was the deciding factor for me on which bike I would prefer. The Kawasaki KX250F was the winner for me because of its comfortable cockpit and how it handled corners and braking bumps. The bike suited my aggressive and loose riding style and it didn’t fight me when choosing lines. The Suzuki was a good bike as well, but the chassis on the Kawi was more suited for my style of riding. Overall if I were to pick from the two, it would easily be the Kawasaki, mainly because it is more of an aggressive type of bike. Its power was a lot stronger and the suspension feels suited for faster riders. Fewer changes are needed to make the Kawasaki to where I would like it than the Suzuki. They are both great bikes that each have lots of potential.
Andrew Oldar, Age: 26, 5’10”, 130 lb., Novice
The Kawasaki KX250F and Suzuki RM-Z250 are both good bikes that feel very different from each other on the track. The Kawasaki feels like more of an all-around package whereas the Suzuki feels like it’s especially good in some areas and lacking in others.
The RM-Z250 engine feels like it revs a bit slow and likes to be short-shifted as it has a decent bottom-end and midrange power but falls off slightly on the top-end and over-rev. I have no problems with short-shifting a bike, but it does make for more work, and it’s nice to have a strong top-end power because it gives me the option to either short-shift it or rev it to the moon. In stock form, this engine is not as powerful as I would like.
The Kawasaki KX250F engine has a crisper, more instantaneous throttle response than the RM-Z250. It revs very freely and builds power very smoothly. I do wish the KX250F had some of the snap that the 2016 and prior engines had, but this engine is still very good and has a very linear powerband. A minor complaint about the engine is the exhaust system. I feel like it allows the bike to breathe pretty well, especially in stock form, but it has a slightly raspy sound to it. Although it has improved in this area noticeably than in years past, I think it still could be better. Ultimately, I liked the engine better on the KX250F because it felt stronger overall, especially on the top-end, and it required significantly less shifting than the RM-Z250.
The Suzuki RM-Z250 suspension felt harsh up front and fairly plush in the rear. The KYB PSF2 air fork offers a wide range of adjustment, but even when I tried to soften it up, it still had a harsh feeling in the upper part of the stroke. The fork didn’t offer a lot of comfort and gave a jarring feeling on both big and small impacts. If I were to buy this bike, the first thing I would do is try to get more comfort out of the fork. The shock felt good on harder impacts, but the bike seemed to step out on me when charging down hills.
The Showa SFF fork on the KX250F had more of a performance-oriented feel but more comfort than the RM-Z250. The fork is firm enough to handle big impacts and was easy to dial in with just a few clicks softer on the compression. The shock did an excellent job of soaking up impacts and helping the bike maintain straight line stability. The suspension on the KX250F suited me better than the RM-Z250, especially the fork.
The chassis on the KX250F was impressive. It has excellent straight-line stability and still corners pretty well too. The Kawasaki feels like a small bike in a good way, which makes it easy to throw around and put where you want it, and this is also true in the air. It also feels very light and didn’t seem to wear me out as quickly as the RM-Z250.
The RM-Z250 is a cornering machine. I was amazed at how easy it was to lean the bike over into a turn and the bike just seemed to do the rest. Unfortunately, the amazing cornering ability came at a cost as the bike doesn’t have very good straight-line stability. I noticed this when coming down the big hills at Glen Helen. The rear end had the tendency to kick out at speed, which it didn’t do too erratically but enough to put a dent in my confidence in the high-speed areas of the track. The RM-Z250 feels a bit heavier than the KX250F but is certainly easier to corner than the green machine. Aside from the RM-Z250 being a better turning bike, I liked the KX250F chassis better overall.
At the end of the day, I found myself leaning more toward the Kawasaki KX250F. It feels lighter, is easier to throw around and ride aggressively, has better straight-line stability, and a linear powerband with more overall power. The one area I liked the Suzuki RM-Z250 better than the KX250F was in the corners, but the Kawasaki shined brighter in all other areas for me.