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

Other days

kale

Kale Day
bounce

Bounce Day
china

China Day
cuddle up

Cuddle Up Day
cursing

Cursing Day
self care

Self Care Day
ride the wind

Ride The Wind Day
get funky

Get Funky Day
hot chocolate

Hot Chocolate Day
donate your hair

Donate Your Hair Day