A50 / A65
The type of specialists for these models Klaas Wezel en Jelle Bethlehem.
BSA A50 and A65 models are motorcycles with a two-cylinder 500 cc block (A50) or 650 cc (A65), with overhead valves and a unit structure, ie the crankshaft and gearbox are in one house.
Production Period and properties
The A50 and A65 models produced from 1962 t / m 1973. They have an alternator and ignition coil. The frame is in its basic form the same as the A7 and A10, with a double cradle. The engine is hard to see if it is a 500 or 650 cc machine. A50 had a bore x stroke of 65,5x74mm. When the A65 was increased the bore to 75mm making it a short-stroke block.
In 1962 the A50 and A65 Star came out who was going to replace the A7 and A10. A year later came the A65 Rocket in a sport version with a more powerful engine. In terms of performance it seemed very much on the A10. In contrast to the older twins switched to the A-50/65 the other way around, i.e. one downwards 2, 3 and 4 to the top.
In 1965 the series was revised and received the new models names.
The A65 Thunderbolt was called with one carburetor and the Rocket with two carburetors would henceforth bear the name Lightning. Also A65 Lightning Clubman was presented. It was designed as a racer and was carried out in a beautiful color combination of black and gold. After one year this engine was replaced by the Spitfire. There are therefore no more than 200 copies were built. The sporty 500cc version A50 Cyclone was while touring version of the A50 Royal Star was called.
In 1966 the series consisted of the A50 Royal Star, the A65T Thunderbolt equipped with a carburetor and A65L Lightning had two carburetors. The A65S Spitfire was the fastest model with GP carburetors and 190mm simplex full hub drum brake in front and aluminum rims. For the US market two (desert) racers were made that had no lighting: A50W Wasp and Hornet A65H. All models excl Spitfrire had half the hubs. This year, all BSA’s equipped with a 12 volt electrical system.
In 1968, the A65FS Firebird Scrambler was added to the range. It was an all-road model with bent outlets and feature lighting. The A65S Spitfire was the fastest model, but this year was equipped with 32mm Amal Concentric carburetors and aluminum rims. All twins were this year TLS 190mm drum wheel.
In 1969, the Spitfire disappeared. He was succeeded by the Rocket 3. as a top model in that year were the A50 Royal Star and three 650 twins, delivered the Thunderbolt, the Lightning and the Firebird Scrambler.
For the season 1970, the engines were improved in several respects.
In 1971 a completely new line of engines. The engines were the same as the 1970 version, but the bicycle parts were redesigned. The frame also served as a tank (which is why they are called oil-in-frame models), there was mounted a Ceriani fork-like, conical drums, flat, chromed headlight and turn signals. They looked much slimmer than their predecessors. The A50 was run so were only three available 650 twins. In 1971 a large party Thunderbolts delivered to the army of Jordan. In 1983 imported about 500 of these machines in the Netherlands and sold in the restoration of fans across Europe (and beyond).
The latest version of the A65 was the A70 Lightning. They were built in June, July and August 1971 but were presented as a 1972 model. Thanks to another crankshaft with a stroke of 85mm motor had been a displacement of 750cc. There are only 202 A70’s produced.
An A65 Star 1964
A Spitfire with the characteristic tank.
A65 Thunderbolt 1972