interresting ? six stroke ? vespa had something in production in the vespa et2 inietione
it was a second crank driven by the main crank over a timing belt with a smaller piston in the head that pumps air fuel mix from the carb then the compressed fuel/air mixture over a sprig loaded valve into the combustionchamber and it worked realy well without any tuning or derestricting 40mph and loads od torque (for a 50cc) was only produced for a year , i had one and sold it here in the uk ....was never imported into the uk by piaggio and even in europe they are rare because they have been more expenciv then the 2 stroke and 4 stroke vespas and the promised advantige of high miles per gallon was not realy true becaue it needed same fuel as the four stroke but also two stroke oil and even more the the two stroke because the second crank needed oiling too but it would pull like a 125 with that system up to 40mph then the cpu told the engiene to stop pulling further
