Most FBOs do instrument
training in their 172s (and everything else) and therefor prohibit
CFIs from spining the crap out of the gyros.
I discovered this to be the case at Chandler. One of the reasons I
went out there was to fly a Super Cub, and naturally I wanted to do
the spin training in the PA-18 as well. But they don't allow the Super
Cub to be spun, for just the reason you advance.
At home, we're not permitted to spin the J-3 Cubs, either, but not
because of the gyros

The feel is that the planes are too old.
(However, my first CFI learned in the Marine Corps, and he taught from
the same book that taught him. He spun the Cub with me in the back
seat after just a few lessons. It's a very different experience, being
in a closed airplane in the back seat, than to be in the front cockpit
of a Great Lakes with double seat belts and a parachute
all the best -- Dan Ford
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