Another Rotax Driver here. I run a BRM
http://www.blitzperformancekarts.com/Dk9125cc.html at F1 Outdoors
http://www.f1outdoors.com/ near Boston, MA and on the New Hampshire Motor Speedway road course
http://www.nhms.com/ I've also done quite a bit of league racing at F1 Boston
http://f1boston.com/