Last night's first full practice session for the 2012 Manx Grand Prix was thwarted by fog.
Competitors only managed a single lap of the 37.73-mile Mountain course before the session was red-flagged on safety grounds.
Riders in the Junior 600cc class were first away, including last year's Junior race runner-up – Paul Smyth – plus rising talent Jamie Coward, who is tipped to make a big impact at the festival this year, which is seen as a stepping stone to the Isle of Man TT races.
Coward was fastest through the speed trap at Sulby at 169mph, although it was Supertwin rider Mike Minns who clocked the fastest time with a lap of 112.44mph, with Yorkshireman Coward lapping at 111.46mph.
Ulsterman Trevor Ferguson, riding a Kawasaki ER6 for top road racer Ryan Farquhar, was third fastest with a lap at 111mph.
After the opening lap, Clerk of the Course Phil Taubman kept the roads closed and opted to allow the Classic competitors to leave on a lap of the circuit, stipulating that from Parliament Square they would be escorted over the fog-hit Mountain on a speed-controlled lap by a travelling marshal.
The lap counted as a qualifying lap.
Competitors who set off included Russ Mountford and Manx star Dan Kneen on '85 Suzuki XR69s in the Classic Superbike session while Ulsterman Farquhar, Olie Linsdell, Alan Oversby and Chris Palmer all went out in the Classic 500cc session.
The Classic, Classic Superbike, Junior Post Classic and Newcomers are due on the track first this evening, with the session scheduled for a 6.20pm start.
The opening race of the festival, the Newcomers event, takes place on Saturday evening, when current British Supersport Cup champion John Simpson from Antrim will ride for the Splitlath Redmond team on a Triumph 675.