W.O. Bentley introduced the new 6½ liter model in October 1925 at the Olympia Motor Exhibition. The straight six engine powering the vehicle actually displaced 6597cc and the chassis was very similar to the earlier Bentley's, though the braking had been enhanced to cope with the extra power. There was also a more substantial differential and a plate clutch. This new model would be the basis for the company's future campaigns at Le Mans up to 1930 when they retired from racing.

Chassis number BX 2421 has a documented history from new. The original owner was E. Bullivant of Mortimer House, Egerton Gardens. The vehicle carried a guarantee date of March 1927, and was fitted with the later pattern push-on brakes and a 26 gallon tank, features which would only become standard the following year. It had a long steering column and a 3 liter exhaust fishtail. The Sports Tourer coachwork was crafted by Vanden Plas. The body was paneled rather than fabric and it was designed with an armrest for the driver. There were side lockers, a trunk at its rear and a double spare wheel carrier. Full weather protection was required and it had pockets to all the doors. Accessories included Zeiss headlamps. The total cost of the body alone was nearly twice that of a standard Vanden Plas body.

During Bullivant's first year of ownership, the car was upgrade with a new radiator and crankshaft driven dynamo, camshaft damper and 'new type carb.' In 1929, the car was traded at Jack Barclay for a newer model. the next owner was R. Winloe who kept the car maintained by the factory, and continued updates with high speed oil pump gears, a sprung steering wheel, rear hydraulic shock absorbers to the rear and a Spicer shaft, as well as converting it to a C type 'box with the help of Birkin & Coupers of Welwyn.

In 2011, it returned to a Bonhams auction, this time at the Quail Lodge in California. It would leave the auction unsold after bidding failed to satisfy the vehicle's reserve.

By Daniel Vaughan | Nov 2011