Best to check their site for events. They have a full calendar on their site that shows what times they are running rentals. Otherwise, as long as they are running them, they have a TON of them, and the track is big, so they run a lot of them at once. Unless you go very late in the day, I can't imagine you won't get your races in due to crowds.
Always book in advance
Usually you can just show up and rent a kart, however there are some days where rental karts are only certain times. You can always call and ask if they are running them all day
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