The 250SX-F: The Lites class bike that’s winning fans big-time
The past two years have seen a major transformation in the Kato 250. The PDS and the carby all hit the round file and in its place came a traditional-style linkage and EFI. Strangely enough, the linkage didn’t change the handling of the bike a lot, but the EFI did get some low-end power back into the motor that many KTM riders were chasing.
For 2012, KTM focused its 250 efforts on three major things:
Electric Starter: For the first time on a 250 motocross bike, an electric start comes from the production line. The electric leg has been successful on the larger KTM bikes and no doubt works effectively on the 250, but it does come with a price: weight. And when you consider in recent times KTM has added a linkage and EFI — both of which also add weight — the electric start has made the SXF the heaviest bike in the class. Love the efficiency, but in a class where weight and power mean everything, it’s something most serious racers could live without.
Mapping: Ever since EFI became a reality and until the day it’s replaced with something else, you will read every year that each bike has new mapping. As the manufacturers learn more about EFI in motocross bikes, fine-tuning the mapping will always be part of the process. KTM also produces two additional mapping plugs: an aggressive one and a mellow one.
Suspension: The spring rates remain the same, but the internal valving has been changed. Like ignition-mapping, this also is a yearly exercise for most manufacturers as they try to find the best universal setting for their intended costumers.
Other minor updates include changes to the rear brake, the styling and a new air boot.
What does the motor go like?
The motor is smooth, seamless and rider-friendly. The high rpm, slower revving, torque motor of the past has been replaced with a motor that is stronger off the bottom but flatter through the mid and top. It’s responsive and very easy to use and would suit a large range of riders, but possibly lacks aggression and some overall power.
Has KTM done anything about protecting the EFI?
Last year, KTM riders had issues with any water around the EFI, which caused the bike to cough and splutter. This year the company has packed the area with a marine-style silicone and a protective rubber cover. We pressure-washed the bikes a few times during our time on them and it ran clean every time.
How does the motor compare with the other brands?
The Kawie is the horsepower king in the 250cc class and a clear winner. The remaining four bikes are all very close in terms of power and the most noticeable difference between the brands is the delivery. The KTM is possibly the smoothest and easiest to use of the bunch.
What can I do to get the more from the motor?
Mapping and exhaust are the easiest and most obvious places to start. KTM hard parts offer a simple way to reprogram the mapping to fine-tune the power while a good aftermarket exhaust might put some punch back into the power. It obviously can be done, as Matt Moss was rumoured to say when getting on his US bike, “Is this thing even legal?”
What are the suspension and handling like?
KTM has made great strides in suspension over the years, but don’t think it’s because of the linkage. Adding the linkage was aimed fair and square at the US market, and particularly supercross, as KTM didn’t believe you could get the PDS to work on step-on-step-off-style jumps. Ride a current bike back to back with a PDS model and there’s not a lot of difference in the way they feel.
When pushed, the forks used up a lot of travel yet felt nice on the smaller bumps. The front of the bike feels great on faster and open, flowing turns and carved a smooth line. We tested the bike on the sand track and the national track at Goanna and the KTM felt solid on the sand, but not quite as good on the tighter, rutted turns on the national track. It wasn’t bad; there’s just a noticeable difference between the two surfaces.
The shock hooks up and drives well and offers a good, smooth action. Again, the bike seemed to perform better on the sand track and, after a quick ride-height measurement, my weight meant I needed a heavier shock spring. A heavier spring would have balanced the bike, giving it a better feel on hard pack and allowing the front to bite more.
Is there anything else I need to know?
The stock tyres are now Dunlop MX 51s and not the old tried-and-true Bridgestones — not a major performance hit but worth noting. There’s no kick-start, so if the bike won’t fire with the button it’s time to don your running shoes. I reckon adding a tooth to the rear sprocket would also be something most riders would benefit from.
In the past, I have always felt the KTM250SX used the motor as a headline act and then just bolted the rest of the bike around it. The last two models may not have had the horsepower of the old carby bikes, but the handling, attention to detail and build quality have all stepped up a notch. As a result, the bike seems better rounded. Sure, the motor could do with some punch, but that’s easily fixed. I think the overall package is better than what KTM has had in the past; it just needs some finishing touches.
Second Opinion: Nick Lean
The new KTMs have a modern style that looks pretty trick; the sharp, slimline plastics give the bikes a nice finish. The ergos were a lot different to what I am used to on Japanese bikes, although it seemed to work well once I got the hang of them as I felt comfortable on the bike and wasn’t cramped at all.
The hydraulic clutch on the 250 was awesome — it always had the same consistent, light feel. The seat was hard and not really what I like, although you could get a good feel of where I was sitting on the bike. Rear brake was good; it had good feel to it and worked well. The front brake felt a bit spongy. The suspension wasn’t right for my weight but with the right weight springs I think I could get it to work well. My overall impression was that the bike had a great feel; I liked the throttle response but it didn’t seem to hook up and drive as well as my race bike and the suspension was a bit hard, which may be due to the fact that I only weigh 62kg and the bike in standard trim would be more suited to a 70–80kg rider.