Maybe this topic has been brought up here before, But do
homebuilt/experimental aircraft have to comply with Airworthiness Directives
set forth by the FAA?

snip

No certification, no ADs. Short and clear enough?

True for an airframe or experimental engine. But if the aircraft uses any
component such as an appliance or propeller or engine etc. then the AD's
against that comoponent would apply even if the aircraft it experimental.
Appliance ADs most often use a phrase such as "..is applicable on any aircraft
certificated in any category... That would cover the experimental category.

John Dupre'