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I just bought a 2017 KTM 250SXF to replace my 2016 250SXF, which I sold to my brother-in-law. For some reason the 2017 doesn’t feel as fast as the 2016 did. I’m a Vet Novice, and I used to be able to clear all the jumps at my local track on my ’16, but can’t get over some of them on the ’17. Is the 2017 KTM slower than the 2016 KTM 250SXF?
No, both the 2016 and 2017 produce identical horsepower and have identical powerbands. But, you are not wrong about the 2017 KTM 250SXF feeling slower. The problem for riders below Pro speed is that KTM changed the 2016’s 13/50 gearing combination to a 14/51 ratio in 2017. Depending on the track layout, many Novice and Vet riders have trouble getting the 2017 KTM 250SXF and Husqvarna FC250 all the way to 14,000 rpm before they run out of straight or, in your case, before a jump appears on the horizon. Thus, the jumps you were hitting at peak horsepower on last year’s bike, you are hitting somewhere below peak rpm on this year’s bike. The solution is simple. Leave the 51-tooth rear sprocket on your 2017 KTM 250SXF and put a 13-tooth countershaft sprocket on the front. The tighter gearing will make it easier to get on the pipe sooner and develop enough thrust to get full use out of the high-rpm powerband. The current 14/51 gearing on your bike is the equivalent of running a much taller 13/47 on your 2016 250SXF.
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