New age bike from Austria
After a successful race debut with factory rider Jonathan Barragan at the last year`s MX1 GPs we were more than excited to get or hand on the all new KTM SX-F 450. Next to Suzuki`s RM-Z 250 is KTM`s 450 the only all new 2007 model. The others are just modified 06 versions.
 German GP-Rider Marcus Schiffer (GER, KTM)
Photo by: Jörg Domanowski / realmx.comWe had a lot of fun with the new thumper from Austria and also our part time test rider and GP regular Marcus Schiffer who had his first outing on the new SX-F 450 when we did our testing. The 19 year old was more than impressed by the Austrian product. He is keen to win the German MX-Masters championship on that model so look at the race reports in October if he realized his goal.
Tech
The SX-F is different. All of the competitors use aluminum for the frame while KTM sticks to steel. And we don`t see a reason not to. Hitting the scales at 104,5 kg the 450 KTM is on the same level than the competition despite an extra weight of more than 3kg due to the electric starter package. Another plus of the steel frame is that it is much easier to adjust the carburetor thanks to the thinner side frame tubes.
 The KTM SX450 07 from left
Photo by: Jörg Domanowski / realmx.comA new white power fork is now featuring a Showa-style closed cartridge system that works a lot better than the previous White Power models. Very unique are the adjustable triple clamps. Not only the bar position, also the offset is adjustable. The KTM owner can choose between 18 amd 20mm.
The Shock is mounted in a different angle and is longer due to the new swingarm. Another nice feature are the black rims although they might not look too good anymore after the first couple of races. The all new plastic style with no more existent side number plates caused some discussions but we always like to see new ideas on the track.
Chassis
The handling is neutral and precise although the front end has a very light feeling. We tested the bike with the short offset so maybe be the other adjustment might add some stability to the orange thumper.
 The KTM SX450 07 from right
Photo by: Jörg Domanowski / realmx.comThe new seat is not as hard as the KTM foam used to be in the past. We liked it better before. The new frame and plastic layout gives the rider a lot of room to move around. It never feels like a big 450 as the earlier models.
The Brembo made brakes are awesome and might set the standard of the class.
Engine
KTM went a different way when designing the engine when setting the stroke to only 60,8mm which is pretty short compared to the competition.
 The one and only in its class: magic starter button
Photo by: Jörg Domanowski / realmx.comAfter many year with a single camshaft KTM finally built a DOHC engine for their big bikes. Also the cases are all new and deliver a slim and stylish look. Despite the hydraulic engagement pulling the clutch is not easy. It seems KTM pit in very strong springs to make it last very long but there is some extra hand power necessary compared to the competition.
On the track we noticed a nice and quick throttle response and a very wide rpm range. The meat of the powerband within the mid range but there a also good high end qualities. There is an optional ignition curve but to be honest, the difference is hard to tell. Maybe a slightly quicker feeling with the ‘aggressive’ adjustment. Four gears were plenty for all the MX tracks we rode.
Upshot
The new SX-F450 handles better than any KTM we`ve ever ridden.
 Marcus Schiffer (GER, KTM) gets it flat
Photo by: Jörg Domanowski / realmx.comIt feels more like a 250F bike and is easy to ride all the time. Many special features like the electric starter, a hydraulic clutch and high quality suspension units. That makes it a top contender of its class and there is no difference in performance and quality to the Japanese competitors anymore.
Once the suspension is dialed in we consider the SX-F450 as the best all-around package of all the 450s this year.
Technical Data
Engine:- Type: 449 ccm 1-Zyl. 4-stroke DOHC 4 Valve
- Bore x Stroke: 97,0 x 60,8 mm
- Compression Ratio:12,5:1
- Carburetion: Keihin MX FCR 41
- Ignition: Kokusan digital DC-CDI
- Transmission: 4-speed with wet multi-disc manual clutch
Chassis:- Suspension/Front: WP USD Ø 48 mm
- Suspension/Rear: WP Monoshock PDS
- Brakes/Front: Single semi-floating 260mm disc, dual-piston
- Brakes/Rear: single 220mm disc, single-piston
- Tires/Front: 80/100-21"
- Tires/Rear: 110/90-19"
Dimensions:- Wheelbase: 1481 mm
- Seat Height: 925 mm
- Rake (Caster Angle)/trail: 63,5°
- Dry Weight: 104,5 Kg
- Fuel Capacity: 8 Liter
- Color: orange
Author: Jörg Domanowski
With friendly permission of Jörg Domanowski (JD) / realmx.com. | 
