2015 KTM 450 SX-F Factory Edition
KTM’s “Ready to Race” motto has once again surfaced with the 2015 450 SX-F Factory Edition - a motocrosser that’s majorly upgraded over the base 450 SX-F.
While previous Factory Edition models had arrived with significant updates, KTM pulled all the stops on the 2015 model. The 450 SX-F Factory Edition arrives with less weight, improved performance, and increased reliability.
When planning began, the Austrian-based KTM had one major goal – design a motor that provided increased performance while saving weight and centralizing mass. The powerplant features a completely new design of the die-cast engine cases allowing for a more centralized shaft configuration and extremely compact design.
Internally, a new crankshaft features 10 percent more inertia and a 6.4mm shorter connecting rod for enhanced power delivery. A plain big end bearing with two force-fitted bearing shells run directly on the crank pin for reduced engine width and extended amount of time between service intervals.
The new five-speed transmission is 8mm narrower, 350 grams lighter, and receives a surface treatment on the first and fifth gears to improve durability. The damped diaphragm steel (DDS) clutch features a lighter basket with a reworked inner hub and pressure plate in order to provide a more consistent supply of oil and better coiling of the clutch.
The new cylinder is 6mm shorter and features an optimized water jacket providing an extremely rigid structure and a low oscillating mass. The cylinder head receives a new camshaft which activates four titanium valves via extremely rigid rocker arms.
The rocker arms are diamond-like coated (DLC) on the intake side for engine speeds up to 11,500 rpm. The new engine is 23mm shorter, 9mm lower, and 23mm narrower than the standard model as well.
To keep the revamped engine running cool and at the proper temperature, KTM re-directed the air to flow through the radiators more efficiently. The radiators maintain the same surface area and coolant capacity, but allow for 10-percent better cooling efficiency. The aluminum alloy construction of the radiators make them more durable while the guard design improves air flow and structural rigidity to the system.
Allowing the engine to breath is a completely new exhaust system from front to rear. The header pipe features a Flow Design Header (FDH) which resembles a small expansion chamber similar to that of a two stroke.
The FDH increases power, throttle response, and maintains low noise levels. The silencer is 40mm shorter than the previous design for quicker throttle response and mass centralization is increased through the shorter design enabling the silencer to be closer to the center of the bike and improve overall riding characteristics.
Firing the engine to life is handled by a new starter drive, battery, and wiring harness. The starter drive has a new shortened output shaft while the electric starter drive gears and torque limiter are lighter by 150 grams. The starter battery has lost a full 2.2 pounds and the lighter wiring harness is more centralized by being placed directly above the airbox.
New engine covers keep the new engine looking great and are designed to reduce wear from the rider’s boots. A culmination of KTM's efforts to shed weight from the previous engine results in a weight loss of 4 pounds.
Feeding the engine is a new 44-millimeter Keihin throttle body. The unit has been completely redesigned and reworked to provide instantaneous throttle response and maximum performance in all conditions. It features a new injector position, separate systems for cold start and idle adjustment, and is 100 grams lighter than the previous model.
Perhaps the most significant feature is the new direct-connect design. This system has no linkage in the cable system at the throttle body resulting in superb rider feedback and feel.
KTM is well aware that the start is the only place that you can pass all of your competition at one time. To give the bike the utmost advantage in this area, it added Launch Control to the Keihin EMS, which features a new ECU which processes faster in order to provide the most efficient start.
By simply activating the switch located up near the front master cylinder, the maximum engine speed is reduced in order to reduce rear-wheel spin and get the power to the ground. The EFI control lamp positioned on the upper triple clamps lets the rider know whether the function is on or off. In addition to launch control mode, the new model features three different map selections, including soft, standard, and aggressive. This way, the rider can change the power delivery depending on track conditions, riding style, or personal preference.
In the chassis department, KTM made it clear that they were trying to improve handling, yet put a strong emphasis on saving weight. The attention and focus put onto shedding weight from the previous model paid large dividends.
The 2015 KTM 450 SX-F Factory Edition weighs only 226.2 pounds and is 10.3 pounds lighter than the standard 2015 KTM 450 SX-F. KTM was able to achieve that by meticulously cutting grams of weight from nearly each and every part. The new chromoly steel frame design is lighter by 380 grams and increases torsional rigidity by 20 percent. The new smaller subframe and swingarm have each lost some weight at 250 grams each.
The new footpegs feature a scraper design to reduce dirt build-up and are larger in size for improved grip. The new 22-millimeter CNC-machined offset upper triple clamp includes a rubber damping system to reduce vibration in the handlebars almost to the vanishing point. The rider is still able to choose between a frontwards or rearwards setting as well.
The new triple clamp holds the WP 4CS (Four Chamber Fork) which feature revised damping settings and ease of adjustment in the compression and rebound areas. The new generation WP shock has been revised to work in balance with the new frame and swingarm.
CNC-machined hubs are mated with Excel rims to ensure wheel strength while the Dunlop MX32 tires come as standard equipment. The KTM Factory Edition is the first production bike to come stock with these highly-praised shoes. Weight-reducing wave rotors by Galfer provide the stopping power in the front and rear.
Other new items found on the Factory Edition are an airbox, intake boot, Twin Air filter, air filter cage, handlebar, throttle assembly, grips, and a front number plate. The front plate now has a cutaway where the front brake cable passes behind it, which eliminates the need for a front brake cable guide.
The exclusive Red Bull/KTM factory race team graphics and blue Selle Dalla Valle factory race team seat give the bike a unique, factory look. Each one also arrives with an hour meter - KTM is well aware that its customers will be putting plenty of hours on these exciting new motocross machines.