2 messed up things
In the park editor make a rail at least the lenth of a block of ground and turn it into a area selection peice and save it.
Put the park size as small as possible and get a huge peice and earase the fence.
"This won't ruin your game" and put the rail against the blank wall and grind it when you fall off you're balance meter should be on forever until you ollie or something.
The the other is do a wall push against a wall and switch like a revert but on flat ground and that would stay on to.
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