Ian Lowry won the Sunflower Trophy for the second time in three years, romping home by 10 seconds from Sam Lowes.
Lowry's Relentless TAS Suzuki team-mate Alastair Seeley failed to start the feature event after suffering minor injuries in a Supersport race crash.
Lowry won both Irish Superbike races to complete a treble while Lowes and Danny Buchan were Supersport 600cc winners.
Jamie Hamilton and Jeremy McWilliams won the Supertwins and William Dunlop and Jamie Patterson had 250 successes.
Nigel Percy and Robert English were the winners of the 125cc events.
Danny Buchan, Michael Dunlop, William Dunlop and Cody Nally completed the top six leaderboard in the main Sunflower race.
Nally joined Lowry and runner-up Seeley on the podium in Irish Superbike race one while David Haire and Michael Dunlop were second and third respectively in race two.
Kirk Jamison was crowned Irish Superbike champion after that race despite crashing on lap seven.
Jamison's nearest challenger Matthew Percy had already crashed out earlier in the race.
The first Supersport race of the day saw Lowes, Jack Kennedy and Seeley go into the last corner together as they battled for victory.
Kennedy crashed out sustaining a suspected broken collarbone, and Seeley was unable to avoid him and also came down, suffering sore ribs and suspected concussion.
Glenn Irwin took advantage of his opponents' misfortune to claim second, with Keith Farmer third.
Buchan saw off Christian Elkin and Andy Reid in race two.
In the Supertwins, Hamilton beat KMR Kawasaki team-mates Ryan Farquhar and Jeremy McWilliams in the curtain-raiser for that class.
McWilliams improved to take the win in race two, with Hamilton second and Farquhar third.
Brothers Ben and Tom Birchall were the winners of sidecar race one, with Tim Reeves and Ashley Hawes the winners of the other race.