I'm thinking of these things: https://en.m.wikipedia.org/wiki/Quadricycle_(EU_vehicle_classification) https://en.m.wikipedia.org/wiki/Quadricycle_(EU_vehicle_c

I'm thinking of these things: https://en.m.wikipedia.org/wiki/Quadricycle_(EU_vehicle_classification) https://en.m.wikipedia.org/wiki/Quadricycle_(EU_vehicle_clas... With a limitation of 50cc capacity a four-stroke may be hard. But they should all be replaced by the electric subclass very easily these days.