Right now I'm running a 62 pilot and 185 main on my 2000 te 610 at 680 ft above sea level. I have a ferraci exhaust system .Overall it runs pretty good but seems to lag a bit at the top(probably b/c being old) but I'm pretty satisfied and it still screams the beginning 2/3 of rpm. I'm going on a trip to 5000-6000 ft above sea level and need to know what jets to use. I only have a spare main 172 and 178. Any suggestions? Can I leave the pilot at 62 with the bike operate ok. Should I change the main to a 172 or 178. I'm Clueless about carbs???