Police are appealing for anyone who saw a fatal crash during the Southern 100 yesterday to come forward.
They want to speak to those who were watching the 600cc race near to Stadium Bends.
Driffield rider James Cowton died because of injuries sustained in the crash which also involved three other riders – Ivan Lintin, Jamie Coward and Mickey Evans.
Officers would also like to see video footage from anyone who was filming the race.
Anyone who can help is asked to contact Police Headquarters on 631212.