Police have named the woman who died in an accident on the Mountain Road early on Wednesday morning.
Amanda Heather McNichol, 49, from the York area was a pillion passenger when she was involved in the incident at the 32nd Milestone.
There were four bikes involved - another pillion passenger was also hurt - but their injuries, while serious, were not life-threatening.
Enquiries are still ongoing and police say they're grateful to the large number of people who have come forward with information.
They're also thanking the people who helped at the scene of the accident.