KTM has gone all out for 2023 and changed just about everything in the four-stroke range. We have seen the factory gods racing them all season but what do they mean to mere mortals?
DBR tester Jake Gowan headed down to the awesome Cusses Gorse track near Salisbury to find out…
Before I headed out on track, I found out exactly what had changed. Beginning with the frame, this is totally new to improve stability, anti-squat behaviour and overall dynamics. This is thanks to repositioned rotating masses in the frame and the forged head connection, together with an all new shock mount which is no longer connected to the main frame tube.
Thicker frame walls are also new to improve reliability and specific rigidity in high-stress areas such as the steering head and the shock mounts. The footrests have increased in size by 26% and are on a repositioned mount to make them less susceptible to catching in deep ruts or on the face of jumps when you’re laying it sideways. All three of bikes (250SX-F, 350SX-F & 450SX-F) now share the same frame and sub-frame so jumping between them is barely noticeable.
WP have hooked the 2023 machines up with updated suspension, the 48mm XACT front forks benefit from new hydro stops in the fork legs to improve bottoming resistance and more progressive damping in the last 40mm of travel.
A major change for the rear shock is the totally tool-free adjustable dual compression control, this allows riders to adjust high and low speed settings in a matter of seconds. This also applies to the front forks and the air pump needed to adjust them is provided as standard.
KTM has gone big when it comes to engine changes, I won’t go too much into all of the details but tell you what you all want to hear. The 250SX-F now features a more compact engine, reducing its size by 8mm. All major components and shaft arrangements are re-designed to give it an outstanding performance engine with over 47 hp and 14,000rpm rev limit.
The 450SX-F offers a peak power of 63 hp and has managed to reduce the weight of the engine by 300g from the last model. The new engine is close to the centre of gravity resulting in better handling and manoeuvrability. Filling the gap between the two nicely is the 350SX-F throwing out a hard-hitting 57bhp and only being marginally heavier than the 250SX-F, this machine definitely isn’t to be looked past.
All three have had the engines rotated backwards in the frame by 2 degrees, this improves mass centralisation. This change has also dramatically improved the handling dynamics and squat behaviour on acceleration. A redesigned five-speed gearbox by Pankl is added to the bikes to reduce the operating force of gear changes by having a more optimised shift shaft.
As you can see the Austrian brand have been very busy over the last few years developing these all-new powerhouses and once I had seen how trick they looked I couldn’t wait to swing my leg over and have a rip around a perfectly groomed Cusses Gorse.
First up, I hopped on the 250SX-F and initial thoughts were how slim it felt. I know most brands each year try to make their bikes slimmer to give the rider a good feeling of control with their legs but KTM have definitely stepped that up to another level for ’23. When I got out on track I couldn’t believe how responsive the power was, the last 250f I rode was a 2020 Husqvarna and this new model blows it out of the water.
Power is pretty much everything in the MX2/250 category and to think how much faster KTM can keep getting with the 250SX-F is scary. The power is really usable, it doesn’t hit hard where its ripping your arms out but has a grunty bottom end feel more like a bigger bike. I could use 2nd and it would be really responsive and rev it hard before grabbing 3rd or it would pull 3rd in most corners with a little bit of clutch to get it back in the high rev range where it likes to be.
The track was ripped and watered quite deep, so in the first session out on track it was a little bit power sapping. I thought on the corners before the up-hill jumps the little 250 would maybe struggle but I was wrong. I could come out of the turn at even a fairly slow speed and it has enough bottom end snap to easily jump everything, if you haven’t rode at Cusses the jumps aren’t too small. This was with the bike in the stock map which is the top button on the switch (it illuminates white).
I was very keen to try out the new QuickShift feature especially while the track was ripped and heavier going as this was when the KTM technicians said it worked best. To use the mode it’s a quick press of the button on the underneath side of the map switch on the left side of the bars. It only works between 2nd and 5th gear to prevent hitting a false neutral.
I could tell a difference with having it engaged as you can slightly feel the revs marginally dip for you whilst under full power. It may take a little more getting used to but I wasn’t a huge fan of it between 2nd and 3rd gear as I felt the rev dip was a little too much and unsettled my body weight forward. Between every other gear it was really effective, offering really fast gear changes. The QuickShift works best on the start and will give KTM riders an advantage into that first turn.
Handling wise it was a dream, it feels so nimble and light with the slim bodywork. I was really impressed with the changes WP have made to the air forks, they held up well in the stroke under hard braking and this meant the rear felt more planted. In the longer ruts in the turns it didn’t want to stand you up and force you to work harder, I felt every turn I came into I knew exactly how the bike was going to react and I don’t think you can ask much more than that regarding handling.
I always hear the question floating around, “Does the 350 feel like a tuned 250 or a tamed down 450?” Well for 2023, KTM have put the 350 into the 450 power category but with a 250 feel. How many riders can actually ride a 450 to its full potential? Not that many…
I could jump on the new 350SX-F after a long time off a bike and feel like I could push on it without it wanting to ride me.
With all the KTM frames being identical for ’23 and the weights between a 250 and 350 being practically the same, I could barely tell any difference until I twisted the right wrist. Pumping out a staggering 57 hp it really can rip, KTM have worked hard on the anti-squat behaviour and it showed a lot on the mid-range machine. It doesn’t squat like the previous models under acceleration therefore giving it an improvement in rear wheel traction. Later in the day when the track was drying out, I could still have full faith in the rear not stepping out when I was on the gas up the faces of the jumps and in the acceleration bumps.
I know its in most of our blood to not want to give up power to our competition but in motocross as we all know there is a lot more variables than a road based sport. Variables such as bumps, ruts, jumps etc… All of these tire us out later in a race, as does the power and torque of a 450 so when your competition is fading late in a race and you’re still as fresh as a daisy on the 350 blowing past them all then thank me later.
Cornering felt exactly the same as the 250 felt, which is really nice when I could still put it exactly where I wanted but had a lot more power exiting the turn. This made everything feel fairly effortless in a way, I didn’t have to quickly hook the next gear before the face of a jump as the 350 would hold a gear longer. As I mentioned with the 250 about the forks holding up in the stroke, this also applies to the 350 and seems to be even more noticeable when carrying a little bit more speed into the turns. Once the track started roughing up I could start cutting tight inside to keep out of the deeper ruts or blown out turns, this felt awkward on the bigger 450 machine but it’s as if its where the 350 wanted to be.
I tried the 350 on both map settings and my preference was the standard map 1, the power is very manageable without ripping arms out of sockets. I think the ‘softer’ map 2 setting will come into its own on the baked hardback tracks, pair that up with the traction control setting and I think it will find grip on an ice rink.
The big brother of all the KTMs. I was actually a little nervous when first hopping on the 450 with quite a lot of time off a bike. I selected the softer map and traction control and it really surprised me. The power was smoother than I anticipated and really manageable, much easier to ride than the 2020 model I last rode. As I’ve said with both of the other bikes, they all feel pretty much identical from an ergonomic point of view, but a 450 always has that inertia effect from the bigger engine.
It wanted to push on a little bit more in turns, this was easier to handle than in years passed due to the new design of the rad-scoops and side panels making it easier to grip the bike. Something I haven’t mentioned yet is how grippy the new seats are on all of the bikes, it was more apparent on the 450 with it wanting to throw my weight back. It was that grippy I was struggling with keeping my pants up at times.
I could pretty much leave it in 3rd gear the majority of the lap except maybe 2 gear changes into 2nd and 4th, Cusses Gorse is a pretty fast track aswell so it proves the gears are tall. I used to gear my 450s up so I could ride in 3rd and 4th to make them smoother, the all new bike is very smooth with the standard gearing.
I switched over to map 2 and it becomes a different beast, I struggled with the amount of low end torque and at top end speed it was so fast. Corners and pretty much every obstacle come at you very fast, you need to be on your A game to be riding the new 450 in that map setting. If you are at a high level and riding 2-3 times a week then this will be suited to you, I just found for the amount I ride now and for most riders then the standard map is much more rideable for a longer period of time.
I did a few starts on the 450, I wanted to try the launch control as well as having QuickShift to play with. The bikes weren’t fitted with a hole shot device to hold the front wheel down which was tricky on the uphill start straight but having QuickShift on a start straight is an absolute game changer. Launch control is selected by giving the Traction Control and QuickShift buttons together, the lights will flash for around 15 seconds giving you time for gate drop.
It will hold revs at a certain rpm giving you the perfect start. Grabbing 3rd gear quickly on a start is usually the difference between a good holeshot or a mid pack start, QuickShift meant I could instantly grab it and with how much power the 450SX-F has in third then its just the rear mudguard that the rest of the riders are seeing of you.
If you are wanting an advantage over the rest of your competition then I wouldn’t look any further than buying one of the machines from the mighty Austrian brand. If I was still racing then I’d be putting my hand in my pocket and having one, with the QuickShift out of the start I could get used to having a clear track and not eating roost for 20 minutes.
I loved the slim feel and very well thought of shape of the plastics to allow lots of grip for your legs, I was impressed with the power of all three bikes and how easily they all turned and went where I wanted them to. So looking forward, I really think the Japanese brands are going to have to get their thinking hats on to keep up with KTM.