[ODE] Rotation on Universal Joint

[Mark Fournier]

I've set up a universal joint to support a platter, allowing 5 degrees
rotation in the x and z axes, so that the platter can be tilted slightly in
any direction by applying at downward force at that point. As a universal
joint, it should not be rotating at all in the y axis, but it is, and
gradually begins to spin back and forth as much as 180 degrees. This really
defeats the purpose of the universal joint. Is there some parameter I should
be setting to harden the lock in the y axis?