Vincent Black Shadow by Vincent's own Girdraulic blade-type girder variation that used a hydraulic damper in place of a coil spring. Another Series C change was the appearance of curved lugs for the seat stays. The brakes on Series B and Series C Black Shadows are dual single leading shoe (SLS) drums front and rear. Unlike the Rapide, the drums are not interchangeable front-to-rear on the Black Shadows. The Shadow drums are ribbed cast iron. The front drum has a small flange and is attached with five bolts, while the rear has a larger flange and is attached with ten bolts. The brakes
Vincent Black Shadow engine's ports. Early Black Shadows have a third inner valve spring not shared with the Rapide, but this feature was dropped from later bikes. Due to the low-octane 'Pool' petrol that was all that was available in the early post-war years, bikes of the period could have only low compression ratios. Although the prototype Black Shadow was built with a compression ratio lower than the Rapide's nominal 6.8:1, production Shadows have a ratio of 7.3:1 due to having different pistons from the Rapide, although still supplied by Specialloid. The Black Shadows have different carburettors than the Rapides, with Series B