1967 BSA 654cc Thunderbolt & Watsonian Grand Prix Sport Sidecar Registration no. JCT 30F Frame no. A65TA 18568-Y Engine no. A65TA 18568-Y
Following Triumph's lead, BSA turned to unitary construction for its range of parallel twin as the 1960s dawned, launching the all-new 500cc A50 and 650cc A65 Star models in January 1962. The basic architecture of the preceding A7/A10 was retained, so the new engine remained an air-cooled parallel twin with 360-degree crankshaft and single camshaft mounted at the rear of the cylinder block. The cycle parts were much as before, comprising a duplex loop, swinging-arm frame fitted with telescopic front fork. For 1965 the Star tourers were replaced by the A50 Royal Star and A65 Thunderbolt, both of which came with a single Amal Monobloc carburettor. The single-carburettor twin was preferred by many riders, being more economical, easier to keep in tune and only marginally less powerful than the twin-carb version.
A motorcycle combination from new, this Thunderbolt had had only one owner before passing into the current vendor's possession in 1974 (registration was later transferred temporarily into his father's name). The machine was restored circa 2000 and has not been used for nearly ten years; re-commissioning and the customary safety checks will be required before it returns to the road. It should be noted that the speedometer has been replaced (we are advised by the vendor that the total mileage covered is circa 12,000). The combination comes with a V5C document and a small quantity of spares.