Yes, you can ride, but you need full protective motorcycle gear. That can include padded pants/jeans, but it doesn't strictly mean a once-piece or a zipped two-piece.
If you go faster than 120mph or quicker than 10.00, then you run the risk of being asked to leave.
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Just to make this clear, Anthony and I spoke and he is not involved with this. Other than the drag radial rule change, which is a CR rule, nothing else has changed. My post is exactly as the rules are. If you have questions, you need to talk to me.
As far as helmets, if you're in the 12-13 second range, I'm sure a "looking away" will probably happen. But try to get a helmet. You should have one anyway.