I have a 2001 KTM 520 MXC. A few months ago, I moved from ND (1,000ft elev) to CO (5,000-10,000ft elev). The bike carburated perfectly in ND, but I noticed that my bike developed a hiccup/sputter/hesitation around 1/8 to 3/8 throttle when I came to CO. The problem is not very noticable around 5,000ft where I live, but becomes a lot worse when I go riding up in the mountains around 8,000 - 10,000ft. I was running a 165 main in ND, then I tried a 162 then 160 in CO, but neither cured the sputter at 1/8 to 3/8 throttle. Is it reasonable to hope that I can find a single setting that will work well in the wide elevation range from 5,000 - 10,000 ft? I don't feeling like swapping jets back and forth too much. These are the stock settings: Type: MX-FCR39 Main: 175 Jet Needle: OBDTM 2nd from top Pilot: 48 Main air jet: 200 Idling air jet: 100 Starting jet: 85 Mixture screw: 2.5 turns out These are the current settings: Type: MX-FCR39 Main: tried 165,162,160 in CO, was good in ND with 165 Jet Needle: OCEMN 4th from top Pilot: 48 Main air jet: 200 Idling air jet: 100 Starting jet: 85 Mixture screw: 2.5 turns out I am thinking of turning the mixture screw in to lean the jetting, but I'm not sure if that's the right approach to cure the hiccup at 1/8 to 3/8 throttle. Any help is appreciated. Thanks.