I bought a new yzf250, my first 4 stroke. The dealer rejetted it for 5000', Denver Altitude 165 main (180 stock) and 5th clip position out of 7, (4th is stock) Every thing else is sock in the carb. Altho I have only got a few hours on it , it seems like it is running ok but I did take it easy breaking it in. My question is this. I am going to Glen Helen for the Pro/Amfor 2 days of racing, about 3 hrs. The elevation there is about 1300' , I think. Do you think the bike will run ok if I change back to the stock main (180) or even 182, if I leave the needle in the 5th position? Normally with all my 2 strokes in the past it wouldnt be as scary as messing with this new 4 stroke that runs great now. Thanks for any suggestions you can give me