A MANX GP competitor died after falling from his bike after hitting oil on the track during the Senior race, an inquest has heard.
According to reports from the hearing by the BBC, a general warning flag was flown at the scene of the spillage from another competitor's machine, but nothing indicated the spillage until after John Goodall, 67 from Bletherston, crashed.
Isle of Man coroner Michael Moyle recorded a verdict of death by misadventure and said no one was to blame for the crash.
Goodall came off his bike at Ballacraine during this year's Senior Classic race on 25 August. Witnesses said they saw oil on the road, but no flags indicating a spillage were displayed.
Seven witnesses gave evidence, including competitor Bill Swallow, who confirmed his bike left oil on the course, which led to Mr Goodall losing control of his machine moments later.
Three marshals based at Ballacraine explained separately how the "lack of adhesion" flag was not used until after Mr Goodall's accident, although the general warning flag was displayed.
Two spectators from England said the oil leak was obvious to them.
There was also criticism of a lack of hay bales at Ballacraine.
But Mr Moyle emphasised that no one was to blame for the crash.