New Zealand's Bruce Anstey still leads the Classic TT Formula 1 timesheets after heavy rain on the Isle of Man meant Thursday's session was not timed.
Clerk of the course Phil Taubman made the decision after torrential rain fell in the afternoon and F1, F2 and 350cc machines were given the night off.
The decision meant riders concentrated on their 500cc machines ahead of Saturday's race.
Ryan Farquhar is quickest in the class on a Paton at 111.102mph.
The Dungannon rider's lap on Wednesday is just outside Olie Linsdell's record of 111.660mph set in last year's race.
John McGuinness and Ian Lougher have both posted laps in excess of 109mph.
Anstey leads the Formula 1 standings after lapping the Mountain Course at 122.523mph on Wednesday on the two-stroke Yamaha YZR 50.
Michael Dunlop is hot on his heels on the Suzuki GXSR XR69 at 122.173mph.
Blackpool's Roy Richardson leads the F2 Class with a lap of 110.349mph on the FCL Racing TZ250.
William Dunlop's speed of 101.271mph means he was the only rider to top the 100mph benchmark among the 350s, on board his Davies Motorsport four-cylinder Honda.
Practice will continue on Friday with three races on Saturday.