It's a pretty simple explanation, as long as one avoids depth. Remember your right hand rule for electricity and how forces work in the windings of motors and such? You can use the same rule basically for gyroscopes.

Take your right hand, make a fist, and admire your fingernails. Now stick out your thumb. Now stick out your index finger. Not that one! Don't give people the bird, they'll get upset. There's your gyroscope. It's spinning about your thumb (axis) in the direction the fingers are pointing. If you now try to twist your fist gyroscope towards you (thumb pointing towards your face), the end will push up in the direction your index finger is pointing. Try to twist the other way, and the gyroscope fist will push the other direction. Reverse the rotation, and the forces of course reverse. Which is why two matched counter rotating gyroscopes cancel out the gyroscopic forces of each other. Not the forces of mass or inertia, just the gyroscopic forces.

Which should also now be giving you a clue about how a bicycle or motorcycle wheel could not be helping stability. For as you fall over, the slight gyroscopic effect shoves you forward or backwards, not back upright.

Last point as it relates to kayaks. Lets assume you did install a full ship-steadying gyro. In a kayak, you'd regret it I believe. It's fine on a ship that has a nice tall hull to deflect the waves that the ship is now cutting through instead of riding up over. You don't have that much hull with a kayak. You'd find yourself soaked and exhausted, torpedoing through waves instead of bobbing up over them.

Turning would become very difficult as you would not be able tip the boat to change water line and effective chine.

Lastly, if you turned turtle, you'd never be able to roll it back upright.

> I'll accept that they're minimal and not important, but not that
> gyroscopics have absolutely no effect.

> It appears that geometry is similar to dihedral in giving inherent
> stability, and is far more important than gyro effects. I'll stand
> corrected.

> I don't think that two opposite spinning gyros would cancel out,
> I think it'd be twice as hard to perturb the axis, but I could be
> wrong. If anyone knows I'd like to learn, if it's a long explanation
> go ahead and email me.