Paul,
It depends what code the thing is designed to. In the UK the CAA have done a great job developing a code for light gyros. This is the one that all manufactured gyros for UK registration have to comply with - known as BCAR Section T (CAP 643). There is a new version of Sect T published last year.
If you want to get into design of gyros, it is essential reading.
Like any aircraft, good training is essential, but that is not design