I normally ride my DRZ400S (stock Mikuni BSR36 carburetor)at elevations between sea level and 3000 feet. I recently hauled the bike up to about 7000 feet to trail ride. After a quick warm up, the bike just died while going 25-50 mph and left me stranded for about 3 minutes. The bike ran just fine when I returned that day to 200 ft. elevation. Has this happened to anyone else? Does this sound like a jetting problem?