1967 Aermacchi Harley-Davidson 250 CRTT
Frame no. 67CR5040
Engine no. 7B10037H1
1967 HARLEY-DAVIDSON AERMACCHI 250 CRTT
Frame no. 67CR5040
Aeronautica Macchi, soon Aermacchi, was founded in 1912 by Giulio Macchi on the shores of Lake Varese north of Milan, Italy, to manufacture seaplanes. After WW II the company began producing motorcycles and in 1960 the Harley-Davidson Motor Company purchased fifty percent of the motorcycle division to secure a source of small machines. The remaining half was sold to AMF H-D in 1974. Harley "sold back" all in 1978 to Cagiva.
Aermacchi created their "horizontal" four-stroke single in 1956 first as a 175cc in the Chimera, soon a 250 and 350...the racers usually known as the Ala d'Oro (Golden Wing). Development continued through the sixties resulting in literally hundreds of wins, and today it remains a force in historic racing.
This machine is one of a small batch of road racers built for North American. Records indicate that 35 were built, but it could be more. The 1967 model year offered an upgrade to powerful Ceriani brakes from the previous Oldanis. The 350 frame, with its distinctive L-shaped forged side plates supporting the rear of the engine and the swingarm pivot, is unique to the CRTT. The engine, short-stroke (with a bore and stroke of 72x61 mm), could rev past 10,000 rpm reliably. It has a dry clutch and a five-speed close-ratio transmission with straight-cut primary drive gears. Compared with the European market battery and coil ignition, the American market CRTT had a magneto ignition driven by the camshaft under the famous ride side "bubble case".
While it is believed this bike was sold new in Canada, along with two known others, its racing history is unknown. The engine is from a 1971 racing-model ERS, originally a 350 but rebuilt with a special crankshaft giving 250 cc. It has a Carrillo rod and forged piston. It also has the special cylinder head, unique to the CR, which allows the 35 mm Dell'Orto carburetor to sit vertically with its air intake inside the screened window on the left side of the fuel tank. Fuel is drawn from an Amal matchbox float bowl, legendary tuner Francis Beart's trick, as a more reliable substitute for the Dell'Orto original. A Dyna 2000 electronic ignition, with rubber-mounted battery and a control box under the rear of the fuel tank allows custom tuning of advance curves and rev limiter settings.
Forks and wheels are Ceriani, while the rear shocks are custom units from Works Performance. There is a new Veglia tachometer and factory-style double-bubble fairing of the original wasp-waist shape. The special exhaust has a hydroformed megaphone supplied by British specialist Dick Linton, flexibly mounted to comply with noise regulations.
This is a very rare, top-specification 250 Aermacchi that demands respect. Put it in a museum or race it some more, the choice is yours.