Colliding with a wall while boosting on a slanted surface causes strange vertical behavior

[CycloKid]

Colliding with a wall on a slanted surface causes kart to hop higher than it should be able to. When in a boost, this effect is increased further. Some boost pads are a slanted surface and are right next to a wall, for example, here's a video demonstrating this in Yoshi Falls.
During the big "jumps" on the wall, I'm not holding the hop/drift button. Yet it somehow "jumps" anyways

mkjs-issue-7-media1.mp4