Has anyone tried to do a dynamic balancing of an engine? I wonder how hard it is to do and what equipment is needed.

Thanks

Engine balance is covered in sophomore engineering Kinematics classes. Pretty standard calculations, illustrated with static or dynamic models.

Tires are balanced the same way, statically, and sometimes tested dynamically, and you might be referring to that type of operation.

Before a newly designed engine is spun, the balance issues are addressed, and the success is always verified with the engine in operation (or, "dynamically".) This does not require a structural dynamicist, but one is often involved in the validation procedure.

If that's what you had in mind, you might start first with a kinematics book.

Best wishes,
Dave Olson

It is impossible to dynamically balance a single cylinder engine due to the difference between linear motion of the piston, and rotary motion of the crankshaft balance weight. Double web cranks balance better than half web cranks. Then there is the connecting rod with it's rotary part and linear part. Target is to balance about half the linear moving masses, which should result in equal vertical and perpendicular imbalance. From there, you must experiment to get the best rusults, using more or less balance weight depending on the engine mass distribution.