First real post here at Thumper and I hope to be able to contribute to the forum here in the near future (once I up my bike knowledge). Great information here and I've already had several questions answered in the hunt for my main problem. I purchased my 08 WR450 this fall from a good friend (who took really good care of it) with the intention of mating this bike with a Timbersled Mountain Horse snowbike kit. So far the installation and first ventures out in the snow have been great and I can't wait to really tear it up. With that being said my main problem is my jetting. Currently the bike is setup for around 3,000ft and 65F. I've gone through the entire jetting database and I can't find anyone with my specific requirements. 6,000ft at 20F with medium to low humidity would be a pretty accurate description of where 80% of our riding takes place. I would be grateful if anyone could help steer me in the right direction. My local dealership keeps telling me to check my manual. I have a manual and the chart isn't in there. Thanks folks!