Board Thread:Game Discussion/@comment-32701766-20170727211450/@comment-24723179-20170801030142

The problem is there's only two ways to get the race track:

1. A deal that first appeared during the Zootopia update where you buy Flash, 100 gems, and the race track together with real money.

2. It can drop from the ever-infuriating, ever-changing Platinum Chests.

I got it via the first method, so I don't know if it cycles in and out like the chest-only decorations and concessions do. But if you check the Possible Rewards in the Chest screen under Platinum, that should tell you if it's a possible drop at the moment.