Oops, it doesn't look like 'ride a motorbike day' is a national day..

Other days

unicorn

Unicorn Day
blanket fort

Blanket Fort Day
self appreciation

Self Appreciation Day
comfy

Comfy Day
fiancee

Fiancee Day
frozen yogurt

Frozen Yogurt Day
chocolate milkshake

Chocolate Milkshake Day
self care

Self Care Day
stud

Stud Day
bubble bath

Bubble Bath Day