Problems with production of the glass fibre mouldings meant that many riders removed them, which eventually led to financial difficulties and the factory closed on 16 December 1955.

The main change was innovative full enclosure and weather protection, with glass fibre panels that included leg shields and a handlebar fairing.

[3] Vincent also tried to make it easier for the rider to get the motorcycle on to its stand by adding a huge lever on the left of the machine that could be operated from the saddle and a single damper replaced the twin rear shocks.

[3] Increasingly affluent customers may have encouraged Vincent to go for a 'high end' luxury touring model, but at the same time high volume and very affordable small cars were flooding the market.

Vincent's accountants suddenly realised that they were losing money on every Black Knight sold, so the last example of both the model and the marque left the production line on Friday, 16 December 1955.