KTM 250SX-F 2013 Preview
KTM 250SX-F
The KTM 250 SX-F has been an established force in the MX2 World Championship for 8 years now. And the new generation appears with a completely new, even lighter engine and an updated injection system. In other words: a performance package that will redefine the MX2 class. Together with a new frame and new bodywork, the new 2013 KTM 250 SX-F is a winning bike that dominates the MX2 class.
KTM 250SX-F Features and Benefits
ENGINE
A completely new design, without kickstarter, in a new engine case, manufactured in a die-casting process. What's all this for? To save weight. A new, elastic and simultaneously high-strength, aluminum alloy provides additional damage protection for the engine on the 2013 KTM 250 SX-F.
CYLINDER + PISTON
The stroke-bore ratio of the 2013 KTM 250 SX-F has been defined as somewhat shorter-stroked for the benefit of higher peak power, with the new cylinder now boasting a bore of 78 mm (3.07 in) (previously 76 mm (2.99 in)), hence providing space for larger valves. Despite the larger diameter, the box-type, forged piston is lighter in weight. This reduces the moving masses and enables higher engine speeds as well as more power.
BALANCER SHAFT
The goal was less vibration in spite of increased revs. That's why the new KTM 250 SX-F engine also has a laterally positioned balancer shaft, which also serves as the drive wheel for the timing chain and the water pump.
CYLINDER HEAD
Those wanting to know what drives a winner to victory will find the answer here. The heart of the newly developed DOHC engine is the redesigned cylinder head with twin overhead camshafts and DLC-coated cam followers that actuate the titanium valves. Larger, flow-optimized ducts in conjunction with the more generously dimensioned intake valves (intake 32.5 mm (1.28 in), exhaust 26.5 mm (1.043 in)) guarantee 10% more gas flow and significantly improved performance. The new camshafts on the 2013 250 SX-F have also been designed (new valve timing, larger stroke) for achieving a huge increase in performance compared with the predecessor model, above all at the top end of the rev range max. 14,000 rpm, previously 13,400 rpm.
NEW INJECTION SYSTEM
The Keihin engine management system with electronic fuel injection has been improved significantly on the 2013 KTM 250 SX-F. Even more performance has been achieved with greater air flow through a new throttle body - featuring a 44 mm 1.73 in instead of a 42 mm 1.65 in port - in conjunction with the new injector nozzle. The throttle position sensor TPS is more durable and protected from stone impact with a plastic protector. The connectors are now enclosed in rubber grommets to protect them from pressure washers. The wiring harness has been simplified and the quality of cables and connectors optimized. Additional engine characteristics can also still be activated with an optional PowerParts map-select switch that can be mounted on the handlebar.
WEIGHT
The modern frame design of lightweight, high-strength, chromoly steel section tubes guarantees an ideal mix of longitudinal and torsional stiffness, resulting not only in easy handling and precise steering behavior, but also in excellent ride stability. The four-stroke frames impress in MY 2013 with a stiffening of the frame triangle and thinner-walled down tubes. This leads to an improvement in tracking stability Increased torsional stiffness accompanied by a reduction in weight. The engine braces to the cylinder head have also been optimized, along with their attachment to the frame. The frame bears a new color on the KTM 250 SX-F and it is still the benchmark in terms of weight and stability.
FORK
The further improved 48 mm 1.89 in upside-down fork featuring closed-cartridge technology has been optimized with completely revamped settings for perfect harmony with the new frame and engine. The new oil is significantly more wear-resistant and guarantees more consistent damping throughout both the course of a race and the bike's life cycle. A new lower triple clamp is 80 g 2.82 oz lighter and, just like the upper triple clamp, CNC-machined from high quality aluminium, whereby the steering characteristics and hence the responsiveness of the fork have been noticeably improved.
SHOCK ABSORBER
The WP monoshock has been further refined for 2013 and, together with the KTM linkage system, it excels with its completely revamped settings for improved damping, more traction and even higher reserves against bottoming out. Rebound and compression damping high and low speed can be adapted individually to the track and rider in no time at all.
WHEELS
The wheels are fitted with lightweight, CNC-machined hubs and high-end EXCEL rims, plus new, black-coated spokes with aluminum nipples, guaranteeing the highest levels of stability while keeping weight to a minimum. The Dunlop GEOMAX MX51 tires stand for excellent traction and performance. For the benefit of greater ride stability on the KTM 250 SX-F, the rear axle has been increased in diameter from 20 mm 0.79 in to 25 mm 0.98 in.
BODYWORK
Not only visually does the completely revamped bodywork indicate that the 2013 model year represents a new SX generation. Above all, the ergonomics and function of the plastics have been designed in such a way that the whole chassis and engine package forms a perfect harmony with the rider down to the very last detail. The fuel tank and spoiler have been restyled along with the airbox cover and the front fender, including the front number plate. A particular highlight is the new front fender, which has no ribbing whatsoever on the inside, thereby preventing mud build-up. A pioneering structure and improved attachment of the fender to the triple clamp result in up to 50% greater lateral stiffness.