MIMRA classically has a run what ya bring policy. We always fit EVERYONE into a class somehow8) Mostly based on lap times verse bike size. Its rather "free form" minibike racing at the grass root level. Some are wicked fast, some are out for just going as fast as they feel comfortable.
You might wanna think about attending the Jackson events as it is a much bigger faster track!
Not sure I would tell somebody to drive 4+ hours to race at our little "roller derby" 4 turn track at Palmyra Speedway. Its fun as heck and turn crisis management but........ probably not worth 4 hours each way in a car
As far as the Canada event they have classes that ANY minibike will fit!