Brothers Ken & Barry Horner have been developing their Irving-Vincents for over a decade and have many successes under their belts including winning the Battle of the Twins at Daytona in 2008. They have around ten versions on hand, each for use in different racing categories. The Period 5 bikes come in 1300cc 4-valve and 1600cc 8-valve flavours, producing 150hp and 186hp respectively.

Fine photography by Phil Aynsley
Irving-Vincent