Cylinder: Water cooling for Vespa & Lambretta at SIP Scootershop
Air-cooled cylinders have poorer and more uneven heat dissipation. The fan impeller is a power and speed destroyer that should not be underestimated. A water-cooled engine is inherently stronger and more durable. A water-cooled, colder cylinder head allows a higher compression ratio. A colder cylinder can be filled with more petrol-air mixture than a hotter one. The only disadvantage is the extra expense for radiator, hoses, pump, expansion tank. They also represent a medium source of error. Therefore, H2O-LC tuning is only for professionals.