For all of KTM’s success in the enduro world, serious growth in the fickle motocross market remains elusive. After the introduction of the new generation bikes in 2007 the Austrian maker has continued to work on improving the moto line up and the latest version of the 450SXF looks like it is going to be a pretty serious contender.
I guess I have always thought of myself as the reluctant motocrosser. My aim has always been to be the best off road racer I could be. As I progressed through the ranks I found myself racing GP style courses where I would wobble around the mx portion of the course and then try to make that time back up on the cross country sections. It became inevitable that I would have to learn to moto, and frankly it has been the best thing I have ever done. I have learned far more on the track than I could have ever done just practicing off road.
In a similar way, I have been hesitant to commit to owning a full moto bike, preferring to use an enduro bike even for track riding. I have spent lots of time watching riders on fast bikes who couldn’t actually make them go very fast. Yet, over the past few months I have had the opportunity to spend time on some current model mxers and I am really impressed with how much they are improving in rideability for the average weekend warrior.
Things are tough all over. Like everyone else KTM has had to take a hard look at its vast model line up and make some tough choices. For 2010 the XCF line of four strokes is gone. The 450 and 505 were popular choices for serious racers, having the weight and power of a moto bike and only the bare minimum of off road essentials.
The reality was that the XCF was more or less just the SXF with a five speed transmission. So instead of continuing with two separate lines, KTM choose to give the SXF five cogs and consolidate the models. Completely gone this year is the 505 model.
While they may have been cutting back on the line up, KTM has been hard at work in the R&D department. For a number of years now test riders and engineers here in the states have been hard at work to improve the handling characteristics of the orange bikes. Much of what is new this year was developed right here at our local tracks.
The biggest news for ’10 is the change to the frame. The main body of the frame is now welded to the steering head 10mm lower. This lowers the overall height and center of gravity of the 450. This change is mated to all new design triple clamps with a 22mm offset. A lower bend Renthal bar is also included to compensate for the lower seating position.
Internally the motor gets a number of updates. New piston rings are designed to eliminate oil and compression loss due to blow by. The big end of the connecting rod gets a Diamond Like Coating (DLC) for reduced wear, especially during cold startup. The piston also gets a thicker crown. Then of course the new five speed close ratio transmission completes the internal changes.
It looks like KTM will be the only girl at the party this year not sporting fuel injection. The good news is, as delivered, the SXF runs great. The new addition of a leak jet to the Kehin carburetor gives super smooth low end response. That magic starter button also helps ease the pain of not having EFI.
The Europeans take the noise issue pretty seriously. Once again KTM shows the way with the “Header Pipe Resonator System”. It is the little closed end canister mounted on the titanium header for the sole purpose of reducing sound. So while it looks similar to the Akrapovic factory header, it actually serves a different purpose. The muffler core is now similar to what was on the XCF models, making for a stealthy package.
Topping off the package is a stellar front brake. The SXF gets the shiny gold Brembo “SXS” machined caliper this year. Even by KTM standards this bike stops wonderfully. The 48mm closed chamber forks get new seals and bushings to reduce friction. The PDS shock has a larger needle and a little more valving to get more damnping early in the stroke. This extra valving means that the relatively light 7.2 n/m spring rate will be suitable for most riders.
I got the opportunity to spin some laps at two different tracks. Glen Helen is open and rough were Pala h
as more jumps and tight corners but with plenty of lines to choose from. As first impressions go; it is all about the motor. It is smooth, almost too much so because it is deceiving just how fast you are going. The lack of noise contributes to this sensation.
The power delivery is very linear from the bottom all the way to the top. The spot on carburetion pulls strongly without the clutch. There is no distinct hit anywhere in the power curve, just strong and deliberate delivery. The five speed transmission gives a little more flexibility in gear selection. I found that often it was faster to not downshift in a corner, just a quick stab to the clutch on exit and let the strong bottom end do the work.
This years’ model comes with the Brembo hydraulic clutch master cylinder. The pull is a little stiff but the lever feel is crisper than that of the Magura model KTM has used off and on the last few years. The cure for the stiff pull is to swap to the smaller bore 125 master cylinder.
The changes to the frame and triple clamps amount to subtle improvements in the overall handling. A little bit of the “feel” has been taken away from the front tire so it does not provide quite as much feedback. Just a little time is needed to gain confidence in the front tire and then things are good.
The cornering is light and precise with a compact feeling. The sliding characteristics are good and predicable. This bike will flat track better than any previous KTM, comfortably drifting both wheels through a corner. The package seems as if it is finally able to fully exploit the benefits of the new style chassis.
No small part of that improvement is the continued development of the closed chamber fork. It is plush in just about any condition, be it little square edges or large flat landings. For that matter the shock does equally as well. About the only place where I could get the chassis upset was in large braking bumps.
It looks like pretty much a done deal that KTM is going to a linked rear suspension in 2011, at least for the moto line up. After riding the latest PDS set up of this bike and also the Husaberg, I am left wondering why? The change will certainly make a huge marketing splash and perhaps that is reason enough. These bikes work really well. The stock spring rates are right in the ball park. I rode the bike just as it was delivered, never feeling the need to play with any of the clickers.
As the semi reluctant moto guy, my confidence level was very high riding the SXF. On one particular table top jump, this was the first bike that I could clear the jump and then make the very tight inside line through the following 180 degree corner. I could brake and turn just as hard as on the 250F that I have been riding recently.
This might just be the ultimate off road crossover bike. Smooth enough for enduro, just lighter, faster and more nimble. Just look at the pro starting line at any GNCC or WORCS race, there won’t be an enduro bike in sight; they are all converted mxer’s. I would also rate it as quite a bit more user friendly than the 09 450XCF that I last rode.
I hope we get the opportunity to test this bike in a moto shootout to see how it stacks up against everyone else. I would also like to see how my impressions stack up against the real go fast moto guys, because this is certainly a bike that makes the average guy go faster.
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