BIKES YOU’VE NEVER SEEN BEFORE: 1960 AERMACCHI 250 CROSS
BIKES YOU’VE NEVER SEEN BEFORE:
1960 AERMACCHI 250 CROSS
Aermacchi, which would be bought by Harley-Davidson in 1960, produced only a handful of horizontal layout, 250cc, four-stroke motocross bikes in 1960, and wouldn’t build another motocross bike for 15 years.
After the end of the Second World War, Aermacchi, which had built airplanes for the Italian Air force, managed to remain active in aviation (but at a slower pace than during the war). To make ends meet, Aermacchi began to produce low-cost two-stroke motorcycles for post-war Italy. The debut of the Aermacchi brand took place at the 1950 Milan Motor Show with the presentation of a 125cc street bike.
Following the economic recovery from WWII, there was considerable demand for larger models, with higher performance and with the four-stroke engines. In 1960 Aermacchi changed the company name to Aermacchi-Harley-Davidson, because Harley had acquired 50% of the company shares. In parallel with the models destined for Italy (and for European markets), those for the USA made up more than 70% of the entire production.
The signature engine of Aermacchi in this era was the horizontal engine design, that later became synomous with the name “Sprint.” The cylinder was cast iron and the three-piece crankshaft rested on two ball bearings. The two-valve engine had a 34mm intake valve and 28.5mm exhaust. The crankshaft turned backwards (in opposite rotation to that of the wheels). The fuel was supplied by a 24mm carburetor.
This is a 1966 horizontal 250cc Aermacchi engine. It has an angled downdraft Dellorto carb, while the 1960 motocross bike had a carb mounted horizonally over the intake port with a side-mounted float bowl.
Although Harley-Davidson had Aermacchi build them motocross bikes in 1975 and 1978, they were ultimately unsuccessful in cracking the American motocross elite. But the 1960 Aermacchi 250 Cross and its laid-down Sprint- four-stroke engine got there first and was a success in the Italian motocross championships. Only 20 these machines were made—mostly for the factory motocross team— some with the single-backbone Aermacchi frame and some with a double-cradle frames designed by Muller in 1963.
These early Aermacchi motocross bikes are very rare and endowed with the catchet of factory one-offs, they sell at auction for a high price.