You can go in at 12:30 and watch EVERYONE practice (be there early for this - awesome chance to watch all the big boys up close because not many people will be there). Following practice is the qualifiers. The qualifiers won't have your top riders out there because they make it straight into the night show. But it's a lot of fun to watch - plus you may see a few locals out there trying to make it into the big show. You can go in and out during the practice/qualifiers. Then there is about a 1-2 hour break from 5:30ish-7:00 where nothing is happening in the dome. I don't think you can reenter until 7pm - but if you are already in, they don't kick you out. But I don't really remember on that one.