Its 420cc engine developed from that of the humble C15 250 roadster, Jeff Smith's works BSA moto-crosser produced more power than it could reliably handle, resulting in a comprehensive engine redesign for 1964. For the new season the works 420 had a much stronger crankcase with revised main bearings, the C15's drive-side ball race and timing-side plain bush being superseded by a roller bearing and ball race respectively. Also new was a light-alloy cylinder with chromium-plated bore, which allowed a useful increase in compression ratio thanks to its superior heat dissipation. The changes made the bike a world-beater, Smith taking the 1964 Moto-Cross World Championship with seven wins in the 14-race series. The new crankcase permitted a further lengthening of the stroke to 90mm for a capacity of 441cc, and in this form the Victor Grand Prix moto-crosser went into production in 1965. Smith took the world title again that year on the works B44GP.

Believed ex-museum collection and restored in 1996, this B44GP Victor was acquired by the current vendor at Bonhams' Stafford Sale in April 2005 (Lot 465) and benefits from recent further renovation. The frame number 'B44 2702' dates it to 1967 (the last year of B44 Victor Scrambler production) while the presence of an Amal Monobloc carburettor suggests that the engine was produced early in that year's production run (later units were fitted with a Concentric). The rocker box is from a later 'square barrel' engine. Offered from a private collection and fully rebuilt, this rare B44GP Victor is presented in exceptional condition and excellent running order.