I've searched the jetting database and can't find anything that lines up with my situation. I have a stock 06 YZ450 that has the stock jetting (165 mj and 42 pj). My altitude ranges from about 4,300 feet to 8,000, with most of the time being spent toward the lower end of the range. I mainly ride in temps from 70-90 degrees. The humidity here is very low. Can anyone suggest a good jetting setup for my bike?