Piezoelectric motorcycle motor.

ICE (Internal Combustion Engines) today convert linear force to rotational force by expanding gasses in an enclosed chamber in "rotating assemblies".

By removing the heads off an ICE we can simulate this by pushing the piston down and we can feel how hard that is. (I only know V8's off the top of my head and it takes approx 600psi at 700rpm to "push" a piston down. That figure increases exponentially with higher RPM's)

When the same engine, without the heads, is rotated by applying rotating force to the flywheel it takes nearly 1/3 – ¼ the force. (Reversing numbers of losses through heat, rotating assembly and such we can assume around 25% efficient. I have actually tested this though in my workshop with rotating assemblies)

We could take a motorcycle engine, remove the heads and replace them with a suitable set of heads to hold a suitable "Piezoelectric solution" (PES) and bolt a small electric motor to the crankshaft to rotate the engine (timing the piston striking the PES at or near enough to TDC to prevent internal damage) siphoning off the electric charge from the 4x pistons to charge a bank of capacitors with some sort of converter that could power the electric motor.

The average 1000cc motorcycle has a piston weight of 184g.
184g piston weight x rod length x RPM = 381lbs of "inertia force"

Striking the "PES" at 5000rpm will give 381lbs of force 625x a second. Surely we could custom build a 1000v PES encased in some replacement head for the motorcycle engine and set it up reasonably cheaply?

I know there was quite a bit of work around the Piezoelectric subject though I don't think many understood the mechanical issues around building something from scratch.
I'm putting this idea up as a possible discussion opener....  I think more work definitely needs to be applied especially since all the big power companies are investing money to it. 

An electromagnetic motor drive as is already available on several motorcycles is a much more efficient solution.

Hello to all: The thought is valuable , but these days supper battery made of suprper capacitors are near solution , since all hub motors used for driving vehicles are regeneratives and supper batteries as said are using supper capacitors , these capacitors are recharged with few minutes and via regenerative motors by applying few brakes it will fill  the mentioned battery and life cycles are about a million ,so your idea is great but this one is has happened.