KTM is the most aggressive company in the motorcycle industry right now. While most other companies have the windows boarded up, just trying to survive the economic storm, KTM is on a mission, producing new motor after new motor. The latest in a long line of new machines is the 450 SX-F Factory Edition–or the Dungey Replica as it’s been called. This represents a slight change in philosophy for KTM.  Previously, the company invested heavily in the 350SX-F as a direction for premier-class motocross. But now this bike makes it clear that the 450 concept is alive and well. Having brought Ryan Dungey on board with the lure of a new machine, KTM now has an all-new 450. It is based on the newest machine in the KTM fold, the single overhead cam 450 off-road bike. That engine has fewer rotating parts than the existing double overhead-cam SX-F and it reflects a more modern philosophy. For now, the Race Replica will be brought to America in limited numbers. We know there have to be more than 400, because that is what the AMA requires in order for it to be called a “production” motorcycle, and therefore legal to be raced under Dungey. Dealers will have very limited access to the bike, and most already have taken deposits on more bikes than they will receive. The price is in the $9000 bracket, depending on location.
      The most critical technical differences between the Replica’s motor and that of the 450XC-W off-road bike are in the piston, the head, the ignition, the mapping, the throttle body and the crank. The combustion chamber has a different shape and a domed piston gives it a higher compression ratio. Most of the rotating parts are lighter, from the flywheel rotor to the new pork-chop crank. But the real news is in the throttle body, which is like nothing we’ve seen so far. The injector is on the bottom rather than the top, and the venturi is wider from side to side than it is from top to bottom. It’s still 44mm at its widest point, and it’s still a Keihin system. If you compare the Replica’s motor to that of the current SX-F, the most critical difference is simplicity. There are fewer spinning gears, shafts and parts. Overall, the goal is a lighter feeling machine. Everts and the 350 team attacked that goal with less displacement, while the 450 group went for less gyroscopic effect.
      The chassis isn’t a big departure from that of the current SX-F. It’s still steel, it still has WP suspension and it still uses Brembo brakes. KTM messed with the frame, swingarm, triple clamps and suspension in subtle ways, but made its biggest investment in new body work.
      We got a chance to ride the bike for one day at Glen Helen Raceway. We had two other KTMs long for the ride. One was the existing DOHC 450SX-F, and the other was the 450XC-W off-road bike, which the new Replica so closely resembles. First things first; the bike feels much, much lighter than either of the other 450s. The Dungey bike feels incredibly easy to throw around. The existing 450 MXer is a good bike in its own right, having finished at or near the top of our 450 MX shootout for three years running. But the Replica makes it feel massive by comparison. The new bike isn’t a revver. It has a very agreeable roll-on, then a hard bark in the middle. Right off the bat, we were guilty of over-revving the bike. If you listen to Dungey, he never screams his machine. Instead, he makes good use of the long, even power delivery and incredible pulling power.
      Even though the new bike is said to make plenty of power, it doesn’t feel as threatening as the older 450. Most of that is the result of the rpm level–you ride the new bike in a much friendlier zone. We did get a chance to ride the bike off-road, too. In that environment, the bike seems more like a brute. It still felt reasonably light, but the power was an inescapable fact of life. We know that Charlie Mullins has already debuted his Replica in the first National Enduro–but then Mullins is an animal.
      We’re hoping to have more of an opportunity to test the Replica later in the year. But availability is so limited, we might have to wait for the 2013 SX-F. It’s right around the corner, and will be based on the same machine, but will have a better price tag. In the meantime, we’ll still be able to see it on TV, under Ryan Dungey.
Michael Leib tossed the Dungey Relica around like it was a 250F.
The bike feels much ligher than the existing KTM 450SX-F–which we love.

First things I noticed when I jumped on the Dungey replica was the Renthal bars, custom gripper seat, and slim overall feel of the bike compared to the 2012 450SX.
The all-new 450 powerplant comes on smoother right off bottom with a bit of a hit that if you’re not anticipating will catch you by surprise. I found myself using the clutch to bring the front end back down more than once. The engine pulls through the mid-range and top-end with ton of usable power.
KTM’s new frame/bodywork combination was very comfortable and easy to get used to, giving it a slim feeling. I was pleasantly surprised by the new gripper seat; it keeps you in position without giving the sandpaper abrasive feel that most current gripper style seats seem to have. Renthal bars that come stock on the Dungey replica seem to be more comfortable bend for me than the versions on the 450SXF. KTM has become known for having great brakes and this bike follows the trend.
In the suspension department KTM seems to have hit its mark. The bike rides higher in stroke both front and rear giving it a planted feel that at sometimes is lacking on the current version. The rebound on the forks was a bit fast for me, I felt like under hard braking and on the face of jumps it was a bit harsh.
Overall the bike felt good can’t wait to get some more time on it. –Mark Tilley

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