5th Place: 2010 KTM 250 SX-F

If you want to talk fast, look no farther than the 250 SX-F. The orange bikes from Austria are the most recognized in the enduro world, and they bring some of that character to motocross. For example, the SX-F is the only bike here with a six-speed tranny, good for versatility if you don't want to be limited to short-circuit MX. And saying that the KTM is the fastest bike in the group is accurate, but finding the power is another story. Bottom-end delivery is completely flat, with no immediate hit; the engine only starts doing serious business way past the middle of the rpm range. It's such a rev-happy engine that you have to "ride it like you stole it," keeping the throttle pinned wide-open and remaining at higher rpm as much as possible. It does have the best over-rev of the group, so it will pull farther than expected in every gear, which means you usually don't have to shift as often.

That's not the only way in which the KTM is considerably different than the four Japanese 250s. All our testers commented on the SX-F's individuality and rated it the hardest of the five to get comfortable on when switching from bike to bike. Their complaints ranged from awkward radiator shrouds to an unpleasantly hard seat to not being able to find an acceptable riding position in the cockpit.

Among the slight changes to the SX-F for 2010 are a new triple-clamp said to improve overall handling and revised fork settings. Despite that claim, the fork was deemed too soft by all testers who weighed more than 165 pounds. Nevertheless, the KTM's high- and low-speed stability is healthy, with decent front-to-rear balance in rough conditions. But the SX-F feels the heaviest of these five bikes, and its reaction to rider input is sluggish, so changing direction requires more effort than it does on the other 250s.