Bike engines could be made much more efficient and not necessarily more costly. Blown and turbocharged 2 strokes would do it. They need no complex cylinder head and valves no expensive cam drives etc etc. These engines would have a normal sump with air blown directly into the cylinder through piston ports. There would be no crankacse pumping losses and the blower and turbo are inherrantly simple rotary machines. With 2x the power pulses we would be making 2x the power. Volkwagen’s road diesels are already making 100bhp per litre. A two stroke diesel could be doing 100bhp from 500cc. With all the torque available that would give today’s R1bladabusaa a run for it’s money.

Why dont we have them? I think Stacius hit the nail. Bikers dont are more bothered about tradition than innovation.

For example –
Torque kills gearboxes so running one at high revs allows it to be smaller and lighter than one running at low revs. No arguments there, modern bikes rev to 16000+ to extract more power from lightweight parts.
In that case, why do the same bikes run the clutch and gearbox at 50% engine speed. The torque load is doubled demading heavier components and creating a slower gearchange. Tradition is very hard (if not impossible) to break.