Sat with my fellow UK test riders on the backseat of the minibus on the way back to the airport, like a gang of delinquents, I was doing some thinking (like I always do when travelling, it’s my ideal thought time and when my mind is most proactive). In between thinking ‘if this driver doesn’t stop soon I’m going to have to urinate in Dave Willett’s ruck sack’ a whole manner of stuff raced through my head in it’s usual diverse fashion.
One thought I do remember thinking to myself was this; ‘can a stock bike ever get so good it literally can’t get any better for the average rider?’ The answer to which I quickly concluded is no, firstly because life is driven by evolution and secondly my bladder was now at breaking point like an over filled balloon and I had to concentrate on not putting myself in a position of extreme embarrassment, the likes of which I’d never live down!
By the paragraph above you’ve probably already worked out that the 2013 KTM range is good and my bladder is weak. KTM have stepped it up again for 2013 and there’s a reason for that – the other manufactures are closing the gap on the standard KTM have set in winning motocross races and selling bikes. I’m not speculating at that, that’s exactly what we were all told at the briefing on the new bikes in Italy last week, the Austrian manufacture are aware the others are closing in and want to stay on top. It’s hardly a surprise; if you look closely you can see how much work the likes of Honda and Kawasaki in particular have been putting into their racing and development. Take the weekend just gone, the World championship was dominated by Kawasaki winning all four motos and they won two more in the US nationals, Suzuki and James Stewart won the other two. KTM have got used to winning and dominating and so has everyone else. As much the others will take great satisfaction in taking wins from them, it will hurt KTM just like it would anyone else.
They have the capability to make changes and upgrades to their bikes and put those changes into production faster than the Japanese and that’s been one of their strengths. The last couple of years their focus has been on the 350SX-F and while they produced a stunning bike it also gave the others the opportunity to close in on them with the 250 and 450 fourstroke machines. No wonder then that these are the two bikes that KTM have turned their attention to for 2013 and the proof is in the pudding (talking of which was great both nights we ate in Italy!)
So, let’s get down to business. I’ll start off by explaining the best I can, the performance of each SX-F bike and then we’ll get into the technical improvements. Let’s kick off with the 450SX-F.
450SX-F (£6895 – available in July)
This is the bike that KTM hope will conquer America. Their intent is clear with the acquisition of Roger DeCoster and Ryan Dungey and these two have played an integral part in it’s development, just like Stefan Everts did with the revolutionary 350SX-F. I can tell you right here and now, it’s very much a different animal than it was before. For starters it’s 2KG lighter (even with the optional kickstart) and my giddy aunt doesn’t it make a difference! The KTM motor was always quick but the trade off seemed to be that it was ‘a big bike’ to match the power. The previous model wasn’t as manoeuvrable as its rivals but now this new one is so much easier to put where you want it on the track, most notably in the air. The 2KG loss really shows up here because KTM have also worked hard on reducing the oscillating masses.
The 2012 model in comparison with its rivals wasn’t as easy to get into a turn, the weight always seemed to want to push the rider wide. I guess that’s basic physics when you think about it, more weight is harder to stop, G forces and all that. Well now this bike doesn’t have that black mark against it. It’s much easier to ride and with the improved ergonomics on the entire KTM SX and SX-F range (well get to that later) it really is a much improved motorcycle in that department. It’s shed some weight and is undoubtedly much more efficient for it, something Dawn French can to relate to of late!
The power delivery is better too. It’s still a rocket but one that you can at least control a little easier. Again that’s down to host of changes to the motor that collectively work together to give a much smoother power delivery that tops out at 60BHP. When you’re on full tap it doesn’t really feel like it because you’ve got there so smoothly – unlike before when the KTM 450 wanted to rip your arms out of your sockets like a fat Redneck diving into their first whole chicken at an all you can eat diner.
With the improved power delivery and lighter weight it’s much easier coming out of the turns as well as getting in them. There’s no apparent hard hit of power, you just roll it on (you really don’t need to use or abuse the clutch – you’ll only be slowing yourself down if you do!) click through the smooth gears (no problems there too) and before you know it you’re already braking into the next corner. As with all the new EFI bikes it’s stupidly responsive with no sign of bogging but it’s now it’s sharper than a Turkish barber’s blade with the improved EFI system KTM have fitted and I just can’t see how any club racer (or pro for that matter) can ever have issues with throttle to wheel response ever again. If you feel you are losing milliseconds then I suggest you look at your choice of lines, technique or fitness.
What’s changed inside the engine…
The design of the cylinder head is based on the 450 EXC engine, but features newly developed ports, combustion chamber and valve train. The lightweight titanium valves and the new, extremely lightweight design of the rocker arms (intake rocker arm is sliding on a DLC coated contact directly on the new cam shaft) allow for the rpm limit of 11,500rpm and a high power output of 60 hp.
– New weight optimised exhaust rocker arms (intake DLC coated slide contact)» low oscillating mass for high rpm
– Stiffer rocker arm axles with integrated oil jet for lubricating the intake cam » safe valve activation
– Titanium intake and exhaust valves » minimum masses for high rpm
– New ultra light valve springs and retainers » precise valve timing
– New weight optimised camshaft with optimised timing » wide power band, high performance
– New ports and combustion chamber » maximum gas flow and ideal combustion for max power output
Compared to MY 2012 the new 450 cc engine is much more compact and is fitted with engine cases produced in die cast instead of sand cast. This allows a thinner wall thickness and means a massive weight reduction of more than 2.5 kilogram!
– Engine cases produced in die cast instead of sand cast » reduced weight, better finish of the surface
– New high-strength alloy material » more ductility and protection against damage
– Much more compact dimensions » increased ground clearance
Piston and Cylinder
In the 95mm bore of the cylinder (predecessor 97mm) a new, weight optimised König piston with a stiff box-in-box design provides a compression ratio of 12.6:1.
– New lightweight forged König piston with stiff box-in-box design and new compression ring and oil control ring » state-of-the-art engine design for high performance
– Cylinder with 95mm bore and mechanical chain tensioner » proven lightweight and reliable solution
The lightweight PANKL crank shaft with a stroke of 63.4 mm (predecessor 60.8 mm)is fitted with a Pankl connecting rod featuring a pressure lubricated plain bearing (no more needle bearing), which allows a high rpm limiter and doubles the maintenance intervals.
– New Pankl conrod with plain bearing with pressure lubrication » allows a high rpm limiter to 11,500/min and guarantees minimal maintenance.
– Reduced crank shaft inertia » more spontaneous power delivery and easier handling.
Counter Balance Shaft
The new 450 SX-F engine is fitted with a laterally mounted counter balancer, which at the same time drives the water pump. This solution allows a very compact and lightweight engine design.
– Laterally mounted counter balance shaft » efficient reduction of vibrations.
– Counter balancer works as a multifunctional shaft driving the water pump » lightweight and compact engine design.
The 450 SX-F is fitted with a reliable and lightweight electric starter. This is an outstanding feature and means a major advantage especially when restarting after a crash, even though this solution means higher weight compared to a pure kickstart engine. For those who want to reduce the weight to a minimum the 450 SX-F allows the electric start to be replaced with a kickstarter.
The DDS (Damped Diaphragm Steel) one-piece clutch basket combined with the primary gear is made of high-strength steel. It guarantees unbeatable reliability and contributes to the narrow engine size due to its compact rivet-less design. Additionally, it allows the use of thin steel linings, which makes the whole clutch package compact.
A diaphragm spring makes it possible to implement an additional rubber damping system, guaranteeing reliability for the transmission and good traction. The hydraulic clutch by Brembo in conjunction with the diaphragm spring guarantees a very light operation and good controllable modulation of the clutch.
A new 4-speed transmission was developed to perfectly suit the 450 cc power plant and provides easy and precise shifting.
– New 4-speed transmission » perfectly designed to fit the wide power band of the new 450 cc engine
A new 65 Watt alternator secures the energy needed to run the electronic fuel injection safely and charge the battery.
– New lightweight SX-EFI alternator with 65 Watt » safe energy supply
250SX-F (£6445 – available in August)
Well, it different compared to the 2102 model that’s for sure. Cutting straight to the chase, KTM have dominated this class here in Europe at the World championships. They’ve always produced rocketships in this category, up until maybe last year where they made a conscious attempt to make a more user friendly bike and spread the power more evenly. For 2013 they’ve gone back to what they do best. This bike is fast, no question but you have to ride it more aggressively to reap the rewards of the all new singing and dancing engine. For me and how I ride it’s not as well suited a bike with more mid to bottom torque but if you like to hang it out and rev a 250 then this will be a great weapon of choice. It churns out 5BHP more than last year and is half a kilo lighter and like the all new 450 you can definitely notice it.
It’s smooth off the bottom but with no immense torque where you think ‘s**t, that’s quick’ so in that respect this could be the perfect bike for the average Joe because it only really lights up when you get in the mid to top power range. This is where you can hold a gear (where maybe on last year’s bike you were better off changing up) and let it have it. Trust me it’s fun when you do. The power is on tap at the top, this thing was ripping up the steeper hills on the hard pack circuit.
On the handling front it also felt an improved bike. The stiffer fork springs have helped the bike into corners as the bike feels more level going in and because of that you don’t get such a sense that the rear is going to hit a braking bump and kick you in the ass like mule. It gives you more confidence going into t turn and tracking a rut.
What’s changed inside the engine…
The basic design of the new DOHC cylinder head with four titanium valves, two camshafts and finger followers follows the same design philosophy as the successful 350 SX-F but internally it is designed for the 250 engine without any compromise. Compared to the predecessor the new 250 SX-F has larger ports, an optimised combustion chamber, larger intake valves and new camshafts guaranteeing a significant power increase of + 5 hp.
– New state-of-the-art design » maximum power output
– Larger intake and outlet ports » better gas flow
– Larger intake valves (30.9 > 32.5 mm, exhaust 26.5 mm)
– New cam shafts and new timing » better performance, improved power band
– Newly design water jacket » improved cooling
The new 250 SX-F is now fitted with completely new engine cases produced in high pressure die cast instead of sand cast. This is a precise casting method for thinner wall thickness. This means a massive weight reduction together with the elimination of the kickstart casting.
– New design of the engine cases, high pressure die cast instead of sand cast » reduced weight, better finish of the surface
– Elimination of the kickstart casting » weight reduction
– New high-strength alloy material » more ductility and protection against damage
Cylinder and piston
The newly designed cylinder carries a extremely lightweight box-in-box piston with a 2 mm larger diameter compared to MY 2012 (76 >78 mm), which allows higher rpm and gives space for larger valves due to the larger bore.
– New cylinder design and larger bore » gives space for large valves
– New forged box-in-box piston » reduced weight for low vibrations, high rpm range and best durability
The completely new crank shaft has a 2.5 mm shorter stroke and carries less inertia for more spontaneous power delivery. Like all the KTM factory bikes the crank shaft is fitted with a Pankl connecting rod featuring a plain bearing (no more needle bearing), which allows higher rpm and less maintenance.
– Shorter stroke » higher rpm range
– Reduced inertia » more spontaneous power delivery
– New Pankl conrod with plain bearing » allows high rpm range up to 14,000 min, guarantees reduced maintenance (crank shaft service every 100 hours instead of 50)
Counter Balance shaft
The new 250cc engine is now fitted with a laterally mounted counter balance shaft, which at the same time drives the water pump and timing chain. This solution allows a very compact and lightweight engine design.
– Counter balance shaft for 250 SX-F » efficient reduction of vibrations
– Counter balancer works as a multifunctional shaft driving water pump and timing chain » lightweight and compact engine design
Like all factory bikes the 250 SX-F is fitted with a reliable and lightweight electric starter. This is an outstanding feature and means a major advantage especially when restarting after a crash, even though this solution means higher weight compared to a pure kickstart engine. For maximal weight reduction the new engine no longer gives the option of mounting a kickstarter. As proven by the KTM factory riders the advantage of the electric start is much more important than the weight penalty.
– Electric start only, no kickstart option » weight reduction
The new 250cc engine is fitted with the same clutch as the 350 SX-F featuring a lightweight, one piece CNC machined basket made of steel, which allows the use of thin steel linings for maximum compactness. The Brembo hydraulic system provides easy and precise modulation.
– New steel clutch basket combined with the primary gear » highest strength and reliability
– New thinner steel linings » narrower engine dimensions
The new 6-speed gear box is adapted to the new engine design and provides the same final gear ratios as the predecessor.
– Newly designed 6-speed gear box » precise shifting
350SX-F (£6645 – available in August)
Like the 250SX-F, it’s faster with 4BHP more than the 2012 model. What effectively has happened is that the 450 and 350 have become closer to each other. While the 450 has become easier to ride due to it leaning up the 350 still have all the razz to throw it around like 250 but now just packs more of punch. So in the big bike class it gives you, the punter, a nice problem to have. Which bike do you choose – a 450 or 350SX-F? It’s almost like they’ve meet in the middle at 400! If you’re an aggressive so and so out on the track then the 350 now has the minerals to please you more. If you like to use the torque of the motor then the 450 is the weapon to have because at least now you can throw it about a bit more and it doesn’t feel like you’re trying to jump a tank.
The 350 is a beaut! Thinking back when KTM launched it I remember Stefan Everts grinning like a Cheshire cat all through the launch, he must have a smile like the Joker on this one. It is such a fun bike to ride. You can still scream the nuts off it and the power is there, certainly enough for anyone other than a top pro or you can shift a gear higher and use the fast but not frightening torque. So in that respect, it certainly caters for all level of riders in the MX1 class. Don’t get me wrong, the 450 is some piece of kit and a much improved bike. If you’re of expert standard you should have the upper hand on a 450SX-F over a competitor on a 350SX-F because it obviously has more grunt and if you use that correctly you’ll have the 350 covered, but as I said, there isn’t much in it and the two bikes have come closer to each other.
It feels good too. KTM have stuck with the steel chassis but made more refinements and with the changes to the suspension and ergonomics it has an even lighter and nimble feel. With all the bikes I never felt at any time that they are unbalanced and I had that sew-saw effect going on with the suspension. I really think the new WP forks are a significant improvement and must take equal credit with the motor and chassis work in making all the bikes an even better package.
All the 2013 KTM SX-F range have received major updates (below) and they all contributed to me asking myself the question I posed at the start. Or course, it’s evolution baby! KTM have once again taken a good old John Cleese Minstry of silly walk style stride in their evolution with the 2013 range. It’s a clear shot across the bows to the others to let them know, not only how serious they are in trying to hold onto the domination of the European MX scene they’ve earned by working hard to wrestle from the Japanese manufactures but also they mean serious, serious business as they wage war on American soil. Seems like the gloves are off more than ever before, the result of which, is our benefit as the bench mark gets higher and higher and KTM have raised the bar first for 2013. It’ll be interesting to see who the others counter attack.
New engine management system for all SX-F models
For 2013 the Keihin EMS was radically reworked. A new throttle body features a bore of 44 instead of 42mm for higher airflow. Together with an improved injector and a new injector position (spraying upwards) the new EMS contributes a lot to the massive power increase. A new throttle position sensor (TPS) is more resistant against water and is protected by a plastic guard. The wiring harness is further improved with longer lead wire and critical connectors are now protected via rubber caps. The small in-line screen is now positioned in the quick-change fuel line connector for easier access. The idle adjuster is now isolated from the cold start button and located in the back of the throttle body.
– Newly developed throttle body with a diameter of 44 instead of 42mm » higher gas flow for better performance
– New injector with better spray pattern, new injector position » improved spray for better performance
– New throttle position sensor (TPS), additional protector » more safety against water and stones, better reliability
– New rubber caps for several connectors » better protection against high-pressure power cleaner
– New position of the micro screen in the quick-change fuel line connector » easy access for regular control and exchange of the screen
Chassis and Ergonomic changes for 2013
Aluminium cast swing arm provides perfect stability at minimum weight. For MY2013 the swing arm is reinforced and now allows the mounting of a larger rear axle to work together with the new frame concept for improved riding stability.
– Reinforced swing arm in the rear part of the arms » improved stability and safety
– Larger rear axle (from 20 to 25 mm) » higher strength and track stability
– Linkage with reworked bolts and nuts » weight reduction
The linkage rear suspension with WP shock absorber was reworked for MY2013 for all models. Beside some weight reductions of bolts, bearing cups and washers of the linkage system the settings of the shocks have been completely updated. In addition the 350 SX-F is fitted with a harder spring. Of course it is KTM standard to allow individual clicker adjustment (rebound and high/low speed compression damping) for any kind of rider and race track.
– Settings updated for all models » improved overall balance and traction, higher bottoming reserves with increased comfort in small bumps
– Harder spring for 350 SX-F » improved balance of the bike
The further improved 48 mm WP closed cartridge Upside-Down fork shines with completely reworked settings for all models and harder springs for 250 and 450 SX-F. A newly developed fork oil provides reduced friction and improved durability for more constant damping characteristics during its entire life cycle.
– New, slightly stiffer settings for all models » better fork characteristics on fast, bumpy tracks and for cornering
– Harder springs for 250 and 450 SX-F » improved balance, higher reserves
– Newly developed, high performance fork oil (SAE 5 > SAE 4)» reduced friction, better durability
– New seal rings SKF with optimised material, colour changes from green to red » reduced friction, improved sensitivity
Modern and lightweight frame design made of chromoly steel provides optimal mix of stiffness and flexibility for maximum track stability, easy handling and precise cornering.
– New 4-stroke frames with additional reinforcement in the steering head area » higher torsional stiffness for better track stability
– The cradle tubes around the engines of the 4-stroke frames are made of thinner profiles » weight reduction
– Newly designed head stays (connection between cylinder head and frame) for all 4-strokes » improved handling and more precise cornering
– New frame colour » better appearance
After just two years the bodywork is completely reworked to further improve the bike ergonomics and indicate clearly, that model year 2013 means a new generation for KTM SX.
– New front fender with new mounting system » up to 50% better stability
– New front start number plate » fits perfectly to the new fender
– New modern spoiler design produced in 2-component process (orange/black plastic in one mould)» improved ergonomics provide a slim feel, good contact with the bike and avoids hooking in with the boots
– New airbox covers produced in 2-component process(orange/black plastic in one mould)» provide additional space for the filter, additional (optional) mounting point for external fasteners
The 7.5 litre fuel tanks have been reworked for 2013 to match the shape of the new rad scoops for improved ergonomics. In addition they feature a new inner screw-type fuel cap.
– 4-strokes with new routing of fuel pump and hoses » 4-stroke SX tanks are compatible with EXC tanks (larger volume for long distance races)
– New inner screw-type fuel cap » follows the SX style, easier to handle
– Micro screen (fuel filter) located in-line in the quick release » easy access for easier servicing
Further developed CNC machined triple clamps improve the bike´s stability and provide improved fork clamping, supporting the fork action due to reduced friction and better bending characteristics. In addition the lower clamp features a weight reduction of 80g due to the reworked design. The front fender is attached by two screws on the bottom and two in the front.
– Reworked triple clamps » better stability, weight reduction, improved fork clamping for reduced friction
– New front fender attachment » improved fender stability
Newly designed airbox and cover provides more space for the TWIN AIR filter. New intake snorkels for all 4-stroke models allow for better airflow and higher performance. The exchange of the airfilter is possible without any tools in just a few seconds. The airbox cover features standard clips to be fixed, optionally it can be secured by an additional screw.
– New airbox design provides more space for the airfilter » better airflow, reduced dirt to filter
– Newly designed airbox cover » more space to filter, optional fixing with screw
– Newly designed and stiffer intake snorkels » improved performance
High strength EXCEL rims, CNC machined hubs and new spokes coated in black guarantee maximum stability. The Pirelli Mid Soft 32 tires stand for outstanding traction. A stronger rear axle (20 >25 mm) improves the stability of the bike (as requested by Roger DeCoster and Ryan Dungey)
– Spokes coated in black » better corrosion resistance, new look
– Larger rear axle diameter (20 > 25 mm) » improved corner and track stability
– New bushings in the rear hub » adaption to 25 mm axle
– New plug-in stand » adaption to 25 mm axle
All models are fitted with new 827 Renthal Fatbar handlebars featuring the equivalent bend of the 996 Twin-Wall. New 2-compound grips with KTM logo provide excellent contact to the bike.
– New 827 Renthal Fatbar handlebars » provide additional height with flatter bend for improved ergonomics
– New 2-compound grips » better contact to the bike, new look
Future noise limits will be a real challenge for every manufacturer, therefore KTM put a lot of effort into developing new exhaust systems for all 4-stroke models, which meet the tough limits of the 2013 season and even improve the bikes performance.
– New header pipes for all 4-strokes, for 250 and 350 SX-F new tapered hydroformed sections and HRS (Header Resonator System) » significantly improved power delivery and reduced noise
– New 4-stroke silencers with tapered inner tubes, individually developed for each model » reduced noise level, better performance
Radiators and cooling sytem
The proven cooling system is transferring the cooling liquid from the cylinder through the frame triangle to the new WP radiators.
– The radiators made by WP RADIATOR are produced in a new alloy providing more durability » stronger alloy is resistant to structural changes in the event of a crash
The proven Brembo brakes in combination with the WAVE discs and stainless steel brake lines provide the best brake performance. The rear caliper carrier is adapted to the larger rear axle.
– Reworked rear calliper carrier » adapted to larger rear axle
A completely new graphic design in conjunction with the new bodywork is a clear statement to underline the performance of the new SX generation.
– new appearance with lightweight in-mould graphics on spoiler and airbox
The vital stats
|SX Models 2013||250 SX-F||350 SX-F||450 SX-F EU|
|Engine type||Single cylinder, 4-stroke||Single cylinder, 4-stroke||Single cylinder, 4-stroke|
|Displacement||249.9 cc||349.7 cc||449.3 ccm|
|Bore/stroke||78/52.3 mm||88/57.5 mm||95/63.4 mm|
|Starter/battery||Electric starter / 12V 3Ah||Electric starter / 12V 3Ah||Electric starter / 12V 3Ah|
|Transmission||6 gears||5 gears||4 gears|
|Fuel system||Keihin EFI, throttle body 44 mm||Keihin EFI, throttle body 44 mm||Keihin EFI, throttle body 44 mm|
|Control||4 V / DOHC with finger followers||4 V / DOHC with finger followers||4 V / SOHC with rocker levers|
|Lubrication||Pressure lubrication with 2 oil pumps||Pressure lubrication with 2 oil pumps||Pressure lubrication with 2 oil pumps|
|Gear ratios||13:32 16:32 17:28 19:26 21:25 22:24||14:28 16:26 18:24 21:24 22:21 –||16:32 18:30 20:28 22:26 – –|
|Cooling||Liquid cooling||Liquid cooling||Liquid cooling|
|Clutch||Wet multi-disc clutch, Brembo hydraulics||Wet multi-disc clutch, Brembo hydraulics||Wet multi-disc clutch, Brembo hydraulics|
|Ignition / Engine Management||Keihin EMS||Keihin EMS||Keihin EMS|
|Frame||Central double-cradle-type 25CrMo4||Central double-cradle-type 25CrMo4||Central double-cradle-type 25CrMo4|
|Handlebar||Renthal, Aluminium Ø 28/22 mm||Renthal, Aluminium Ø 28/22 mm||Renthal, Aluminium Ø 28/22 mm|
|Front suspension||WP-USD, Closed Cartridge, Ø 48 mm||WP-USD, Closed Cartridge, Ø 48 mm||WP-USD, Closed Cartridge, Ø 48 mm|
|Rear suspension||WP-Monoshock with linkage||WP-Monoshock with linkage||WP-Monoshock with linkage|
|Suspension travel front/rear||300/330 mm||300/330 mm||300/330 mm|
|Front/rear brakes||Disc brake 260/220 mm||Disc brake 260/220 mm||Disc brake 260/220 mm|
|Front/rear rims||1.60 x 21″; 2.15 x 19″ Excel||1.60 x 21″; 2.15 x 19″ Excel||1.60 x 21″; 2.15 x 19″ Excel|
|Front/rear tires||80/100-21″; 100/90-19″||80/100-21″; 110/90-19″||80/100-21″; 110/90-19″|
|Chain||5/8 x 1/4″||5/8 x 1/4″||5/8 x 1/4″|
|Steering head angle||63.5°||63.5°||63.5°|
|Wheel base||1,495 ± 10 mm||1,495 ± 10 mm||1,495 ± 10 mm|
|Ground clearance||375 mm||375 mm||371 mm|
|Seat height||992 mm||992 mm||992 mm|
|Tank capacity, approx.||7.5 l||7.5 l||7.5 l|
|Weight, without fuel, approx.||102.9||104.9||106.4 kg|
So there you go, that’s the low down on the 2013 KTM SX-F’s. The 2013 KTM SX test will follow in couple of days! I’m still recovering from riding all these bikes after a bit of lay off! Well I ain’t getting any younger ya know!