Origin of "squid"

Does anybody truly know the origin of the term “squid” as it applies to a motorcycle rider? I have seen many suggested origins, but the only one that seems to make sense to me is that is is short for “squirrely kid”.

It’s what you become when you crash your bike, especially for those racing on paved courses

Superconducting QUantum Interference Device
What?

Oh

[Emily Litella] Never Mind![/Emily Litella]