There are many riders who believe a 450 is too much bike, so they find themselves riding a 250F but wanting more power from it. This leads them to engine modifications such as a high-compression piston, more aggressive camshafts, cylinder head porting, a full exhaust system, aftermarket ECU, or even a big-bore kit. Some of these items require the regular use of expensive race fuel too.
It goes without saying all of this can exponentially add to the cost of owning and maintaining a 250 four-stroke dirt bike. Don’t have us wrong; a modified 250F is incredibly fun to ride. However, those who find themselves between a 250F and 450, and want to buy a bike and leave it alone as far as the powerplant goes may be better off with a 350cc four-stroke motocrosser like KTM’s 350 SX-F, Husqvarna’s FC 350, or GasGas’ MC 350F.
We recently took delivery of the 2022 KTM 350 SX-F, recorded its wet weight of 234 pounds on the Dirt Rider scales, measured the seat height at 37.4 inches, and mounted a Dunlop D404 street tire on the rear wheel to see what it was capable of on our in-house dyno. We recorded peak figures of 50.4 hp at 12,300 rpm and 25.9 pound-feet of torque at 8,900 rpm.
For comparison, that’s 4.4 less peak horsepower than the 450 SX-F and 9.3 more horsepower at peak than the 250 SX-F. As far as peak torque, the 350 SX-F makes 8.7 pound-feet less than the 450 SX-F and 6.8 pound-feet more than the 250 SX-F. Closer to the 450 SX-F in peak horsepower and to a lesser extent the 250 SX-F in peak torque, it will be interesting to see how the mid-displacement four-stroke motocrosser performs on the track.