Gerard Kinghan was crowned Enkalon Trophy champion for the first time on Saturday at Bishopscourt in Co Down.
Kinghan doubled up on his Kawasaki ZX-10R at the 41st running of the famous old race meeting, which was promoted by the Motor Cycle Road Racing Club of Ireland (MCRRCI).
The Randalstown man twice beat Irish Superbike champion Charles Stuart to secure the honours in the Ulster Superbike Championship, taking the flag in race one by 4.730 seconds.
Adam McLean, having a run out on the McAdoo Kawasaki as part of his preparations for the upcoming road racing season, had a solid ride in third place as he finished ahead of Alistair Kirk and Luke Johnston. Ryan Gibson, Kris Duncan and Aaron Armstrong filled the top eight positions.
In race two, Stuart led the way on the opening laps but once Kinghan found a way past on lap four, he began to edge away at the front.
He kept Yamaha-mounted Stuart at bay to close out victory by 1.551 seconds after eight laps, guaranteeing his maiden Enkalon Trophy triumph.
Johnston finished in third place followed by Kirk and David Haire, who has returned to the sport after two years. Armstrong, Gibson and Duncan filled the top eight places.
The Supersport race was won by Korie McGreevy, who only just edged out Jason Lynn to take victory, with Kia McGreevy finalising the rostrum places. The top six was completed by Christian Elkin, Joseph Loughlin and Supersport Cup rider Simon Reid.
Loughlin bagged a double in the Supertwins races, while Cameron Dawson and Joshua Rae doubled up in the Young Guns Challenge and Junior Cup races respectively.
Darryl Tweed won both of the Lightweight Supersport races and Paul Robinson was a double winner in the Moto3 (125GP) races.
Jonny Hanna and Kevin Lavery shared the Production Twin victories, while Johnny Irwin did the double in the Pre Injection class.
Kirkistown hosts round two of the Ulster Superbike Championship on Easter Monday.