BSA Motorcycles Bsa Lightning 1965–1972
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| Manufacturer | BSA Motorcycles Ltd, Armoury Road, Small Heath, Birmingham |
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| Also called | A65L |
| Parent company | Birmingham Small Arms Company |
| Production | 1965–1972 |
| Engine | 654 cc (39.9 cu in) OHV parallel twin |
| Top speed | 112 mph (180 km/h) |
| Power | 52 bhp (39 kW) @ 7,000 rpm (claimed) |
| Transmission | Four speed gearbox to chain final drive |
| Brakes | Drum front 8.0 in (200 mm), rear 7.0 in (180 mm) |
| Wheelbase | 56 inches (1,400 mm) |
| Seat height | 32.3 in (820 mm) |
| Weight | 395 lb (179 kg) (dry) |
| Fuel capacity | 4 imp gal (18 l; 4.8 US gal) |
| Oil capacity | 110 imp fl oz (3,100 ml; 110 US fl oz) engine 18 imp fl oz (510 ml; 17 US fl oz) gearbox |
| Fuel consumption | 58 mpg |
The BSA Lightning was a British BSA 650 cc-class motorcycle made in Birmingham between 1965 and 1972.
Development
The BSA Lightning was designed as the all-round sports machine of the 1960s, planned largely for export to the US market to complement the touring Thunderbolt and the later development, the supersports Spitfire. Development of the engine aimed to make it more reliable, quieter and less prone to oil leaks, with top speed sacrificed to improve mid-range and rideability. Nevertheless, with twin carburettors the A65L could still reach 108 mph (174 km/h). Improvements included an oil pressure warning light, but this had a tendency to malfunction, so riders learned to ignore it.[better source needed]
A close ratio gearbox combined with a high lift camshaft made for lively acceleration and performance at higher rpm than the standard A65. The bottom gear was a bit high, however, so riders had to learn to slip the clutch up to 10 mph (16 km/h). Above 5000 rpm customers also complained about excessive vibration, with a tendency to weave above 90 mph (140 km/h).[citation needed]
A useful feature was an 'emergency starting' key position for times when the battery was flat to connect the alternator current directly to the ignition coils.
From 1969 the Lightning was improved with balanced exhaust pipes, redesigned silencer-internals, widened crankcase-half mating faces and a twin leading shoe front brake. When road testing, Motorcycle Sport found the natural cruising speed to be 70 mph (110 km/h), but was impossible to ride comfortably at more 5,500 rpm in the higher gears due to severe vibration, with 6,200 revs repeatedly breaking the headlamp bulb filament; accordingly no top speed runs were attempted.
In 1971, 201 750cc versions, designated the A70L, were also produced for American racing homologation purposes.
In 1972 the BSA Group were in financial difficulties and, in a last attempt to extend the brand life, a new frame was developed for the A65L. As well as raising the seat height to an impractical 33 inches (840 mm), it actually broke during testing at the Motor Industry Research Association (MIRA) test track, marking the end of one of the most successful range of British twin cylinder motorcycles.
Pictured 1963 BSA A65 Lightning
With Joseph Lucas reluctant to continue producing magnetos and dynamos, BSA began developing unit-construction versions of the 500 and 650 twins in 1960 with alternators and coil ignition. The resulting A50 and A65 Stars were launched in 1962. The 654cc A65 was 30lb (13.6kg) lighter than the A10 and two inches (5cm) shorter in the wheelbase. Although largely based on A10 components, the slightly over-square A65 engine enabled the fitment of large valves and could make better use of twin carburettors than the A10 had ever been able to do. The valve rockers were supported on trunnion brackets cast into the top of the cylinder head so that the rocker cover was unstressed and easy to seal. The 1962 model developed 38bhp at 5,800rpm and top speed was 100mph.
In 1963, the twin carburettor A65 Rocket filled the place left by the A10 Rocket Gold Star and was followed by the similar specification A65 Lightning Rocket and A65 Lightning Clubman, which developed the same peak horsepower but at 6,250rpm giving them a top speed of 105mph. The Clubman featured clip-ons and a single seat with back stop whereas the Lightning was in touring configuration. All models remained with a four-speed gearbox although the ratios varied with successive models.
This 1963 A65 Lightning Rocket was acquired for the NZ Classic Motorcycles collection from a private vendor in Santa Anna, California in March, 2008.