What makes a vehicle go over the loop and how can i implement it in a side scroller

I am new to all of this and i am trying to make a simple sonic style side scroller, i have opened up the “rolling” and “vehicle” examples and seen that i can go through loops! however i cant make sense of implementing the same physics in a side scroller! i suspect my skeletal mesh may be the problem but not sure why!

Any suggestions?
Thanks in advance.