
KTM's new 2007 450 SX-F motocrosser is here - with electric start... but no EFI.
Following the very successful start to the 2006 Motocross World Championships, KTM presents this season an entirely new generation of offroad machines. The spearhead of the new range is the 450 SX-F.
KTM has chosen to present the 450 SX-F, the first model of this new generation of offroad motorcycles, at the Spanish Motocross Grand Prix in Bellpuig. Drawing on the enormous wealth and competence of KTM research and development, the company has succeeded in producing an all-round, better-than-ever motorcycle destined for success on motocross racing circuits around the world.
New engine for superior rideabilityThe new 450 SX-F is driven by a completely re-developed 4-stroke single cylinder engine with 449 ccm displacement and twin overhead camshafts. Four super-lightweight titanium valves and a DLC- coated rocker arm work together with the compact cylinder head of the engine with high revving abilities. For the first time the bike comes with an electric starter to set the 59hp power unit with its Keihin carburetor in motion. The application of this new technology means a significant time saving at the start and also carves valuable seconds off a rider's times during the races.
Consistently better chassisA totally new chassis has been developed to help translate the astonishing performance of the 450 SX-F engine into a positive and effective tool on the racing circuit. The frame, made from generously dimensioned, oval tubular profile, is particularly innovative because it allows for slight more space for the cooling system. Improved rigidity means that the weight of the new frame can be further reduced.
The new, weight-optimized, light cast metal rocker, new geometric data from the latest PDS absorber system as well as a totally new WP Suspension upside down fork with integrated cartridge absorber system collectively transforms the SX chassis into the most advanced, high-quality unit in the entire offroad sector.

Even faster through perfect ergonomics When it comes to all the plastic componentsfor the new SX generation, the KTM development engineers have paid special attention to perfect ergonomics and maximum ease of use. It is often the case that the first serious feedback that serves as the key to success comes as a result of tough off-road application. This is why the 450 SX-F is the first model of the new generation that features a fresh design for the tank section that now has a distinctively larger contact surface. In order to achieve the best possible feeling with the rider in every situation, the seat has also been totally overhauled. The new SX, with its numerous modifications, also has a new and very aggressive appearance that represents an unmistakable aesthetic milestone for KTM.

Success right from the start The new 450 SX-F underwent a baptism of fire in great style at the highest level. MX1-factory rider Jonathan Barragan, who has been playing an important and consultative role in the development process, demonstrated the immense potential of the new motocross `generation' in Bellpuig. He was an excellent 4th just behind nine times World Champion Stefan Everts in the first race as well as scoring 7th in the second at the Spanish Grand Prix last week underlines the performance potential of the new KTM 450 SX-F.
"I am really happy with the new bike," he said. "The engine is strong with a softer power delivery. The plastics are new and the tank feels a little wider but my impressions are good and I am keen to keep developing the bike."
Motocross fans throughout the world however will still need a little patience before the final release of this model. Along with the new lines of KTM 125 SX, 250 SX and the 250 SX-F machines, the 450 SX-F will be officially presented to the international media in Mattighofen at the end of June. Delivery of the entire latest generation of KTM SX will follow immediately after.
Technical Data for the Factory KTM 450 SX-F
| Engine | | Engine Type | Single cylinder, 4-stroke |
| Displacement (cc) | 449.3 |
| Bore x Stroke (mm) | 97 / 60.8 |
| Compression ratio | 12,5 : 1 |
| Performance | approx. 59 HP |
| Starter | electric starter |
| Transmission | 4 gears |
| Carburetor | Keihin MX FCR 41 |
| Control | 4V / DOHC with finger levers |
| Primary ratio | 29 : 74 |
| Final drive | 5/8 x 1/4" |
| Cooling | Liquid cooled |
| Clutch | Wet multi-disc clutch, operated hydraulically |
| Ignition | Kokusan digital CDI |
| Chassis |
| Frame | Chromium molybdenum |
| Subframe | Titanium |
| Handlebar | Aluminium |
| Front suspension | WP-USD 52 MA |
| Rear suspension | WP-PDS shock absorber |
| Suspension travel front/rear | 300 / 335 mm |
| Front brakes | Disc brake 260 mm |
| Rear brakes | Disc brake 220 mm |
| Front/rear rims | 1.6 x 21" / 2.15 x 19" |
| Front/rear tyres | 80/100-21" / 110/90-19" |
| Transmission ratio | 14:50 |
| Main silencer | Titanium |
| Steering head angle | 63.5 |
| Wheel caster | 112 mm |
| Wheelbase | 148110 mm |
| Ground clearance (unloaded) | 380mm |
| Seat height (unloaded) | 925mm |
| Fuel capacity | approx. 7 liters |
| Weight | approx. 100 kg |