Aermacchi HD 350 Bicilindrica

On February 25th 1971 a new model 250cc two-stroke appears on the track at Modena, Italy. Renzo Pasolini tested the machine designed and developed by Alfredo Bianchi, technical CEO at Aermacchi Racing. The project was being led by the well-known two-stroke specialist William Soncini. The basis was the Ala d'Oro 125 single. Two of these engines combined gave 250cc and 46 horsepower at the rear wheel. The 350cc had a bore and stroke of 61x59.5 and later 61x54mm. The air-cooled twin used a traditional piston port intake design. Renzo Pasolini was the factory's rider although gearbox and other teething problems meant results were few. By the end of the '72 season the bike was much more competitive however with a weight of 108kg and 50hp. Pasolini won three races and finished second to Jarno Saarinen. After Pasolini's death at Monza in '73 Walter Villa took over and proceeded to win the 250 championship in '74, '75 & '76 as well as the '76 350 title (on a bored & stroked version of the 250). Now known as the 'Aermacchi Harley-Davidson' RR250, the factory bikes had received water-cooling in '73. However, the horrific crash that cost Pasolini and Saarinen their lives at Monza effectively ended the Harley Davidson challenge for the year.

Privateer models following in '74. Development continued with Bimota frames appearing in '77 and a rotary valve engine in '78, although HD sold its interest in Aermacchi to Cagiva before it could be raced. Cagiva continued to campaign both the 250 & 350 with Marco Luchinelli as the rider.

More information: Aermacchi-Harley Davidson RR350

This page is derived from an archive of 2stroke-nl, with additional information from Phil Aynsley and H&H Classic Auctions.

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