Home altitude 5200ft. Finished the Mods a couple of weeks ago, and was a little disappointed....

Started with N1TC needle 2 from the top, smog crap gone, Big Gun Evo-X, 122 main, crankcase breather mod, K&N filter. and mixture screw 2.5 turns out. Starting was good, low end disappointing, mid range definite improvement, high end I'll probably never know.

Commute fuel mileage dropped from 60-65 mpg, to under 50.

Last night changed the mixture screw to 1 turn out. Starting was not as easy, but not a problem. Definitely have more low end power, and the midrange throttle still has "snap". GFoster and I rode from Albuquerque (5200ft) to Sandia Peak (10,600ft) this morning. Bike ran great. Started up at altitude just fine with a little twist of the throttle. Plenty of climbing power at 5-7k rpm. I can't help but tinker, so I'll porbably mess with this setup, but this seems like a good place to start for anyone at altitude. Much improved over stock! I couldn't go above 8000 ft before. Fuel mileage is working with this setup, after a 76 mile ride, I put in 1.05 gallons. I can live with that!

 

I'm in Albuquerque too, just picked up my klx250s on Wednesday. I ordered the new needle and main jets, as well as the snorkle, can't wait to see the difference.

 

So how large a shim would simulate a second notch on the N1TC needle?

Im just a wee bit higher in starting elevation, but Its really close to my riding elevations!

Thanks for the report!