i know of two places that are almost always empty, but with four people maxx ( I like to invite my 2 other friends to rip it up)
also i have a race event we can use
Tag team relay.
basically a two people per team 1 lap each balls out
one person starts at the start line runs a lap hits the pits, and has to pit stop, then the other member takes off for another lap.. can repeat as many times as liked, and its good practice for pit stop and go
as well as a chance to go ballls out for one lap