Weather could cause problems
Roads around the Mountain Course will close at 5pm for the first practice session for the Isle of Man Festival of Motorcycling.
Riders in both the Classic T.T. and Manx Grand Prix will be hoping to get their first untimed laps completed ahead of qualifying next week.
First away will be the newcomers in a speed controlled lap.
Irish rider Damian Horan has been a mechanic for Roger Maher and now gets his chance to be the racer.
Yesterday he admitted the nerves finally kicked in the day before when he finished work:
John Wannenburgh: 'Commitment, compassion and an unwavering sense of duty'
Manx Utilities 'deeply saddened' by death of chairman
"Tynwald will be a less colourful place without John" says president
Douglas North MHK pays tribute to 'amazing friend'