VIDEO: UK outboard maker achieves world speed record

British diesel outboard motor manufacturer Cox Marine has claimed the industry’s first-ever diesel outboard world speed record.

The record was claimed during the 50th anniversary Coniston Speed Week, held this week (31 October-4 November 2022) at Coniston Water in Cumbria, in the English Lake District.

Coniston is considered by many as the world’s premier water speed record event and invites British and International drivers to attempt to break speed records in their class of boat.

The Cox Marine team and their vessel Pegasus surpassed their own three prior speed records, recorded earlier this week, to clinch a world record title, for “World’s fastest Diesel outboard” on Thursday (3 November 2022), achieving an average speed of 62.27mph (100.21 km/h).

Measured across a kilometre-long course requiring a flying start, Pegasus, a 21ft Hallett Vector, piloted by experienced powerboat racer Adam Brown, was required to travel the course’s distances in both directions within an hour to minimise any potential wind advantage.

With oversight from official water speed record timekeepers, both time and the speed in both directions were recorded and then averaged over the two runs, constituting the final speed.

Cox Marine's CXO300 clinches a coveted World Record title at Coniston Speed Week

Powerboat racer Adam Brown

“While there will, of course, be faster boats out on the lake today, it’s a great honour to be able to set a new record,” said Brown after returning to shore following the successful completion of the second run.

“There may be future diesel outboard-powered record attempts, but Cox Marine will always be the first. 62.27mph is a great time for a 300hp engine which is straight off the production line and not having been optimised for powerboat racing.”

Brown adds: “The CXO300 simply did everything it was supposed to. It was quiet, responsive, smooth and the overall experience was not the usual noisy seat-of-the-pants drama that a modified gasoline outboard record run often provides.”

Cox Marine's CXO300 clinches a coveted World Record title at Coniston Speed Week

The Pegasus project was supported by a team of four Cox Marine staff during Coniston Speed Week, and lead by their Head of Research and Development, James Eatwell.

“For the project team of Pegasus, we set out our stall early,” says Eatwell. “We wanted to demonstrate that power and performance can still be achieved without damaging our environment. It’s one of the founding principles at Cox Marine and continues to drive our pursuit of innovation through technology today. We couldn’t think of a better forum in which to emphasise this, than vying for a world speed record and simultaneously debuting the CXO300 use of HVO fuel.”

The Pegasus team says they went to great lengths to protect the integrity of their record attempt, limiting modifications to only the essential foot pedal, dictated by Coniston’s Race Week regulations and a custom fabricated lift plate to allow for the low transom height of the GRP Hallet Vector.

Cox Marine's CXO300 clinches a coveted World Record title at Coniston Speed Week

Aside from that, alterations during the event were limited only to the use of different propellers, which ranged in size, shape and pitch angle and the propellant.

Initial runs were carried out on regular diesel, before switching over to HVO100 fuel. Cox Marine says its internal testing carried out lakeside during the runs showed a 28 per cent fuel saving over an equivalent 300hp gasoline engine and net CO2 emissions reductions of 92 per cent.