Calum Beach pipped Charlie Atkins to the top spot in the first session of the weekend by 0.082secs with a hot lap of 1min 57.094secs.
Third fastest was Jack Smith, just over half a second behind Atkins as Katie Hand was fourth, just ahead of Jamie Hanks-Elliott in fifth.
HEL Performance British Junior Supersport Championship with Motocourse:
1. Calum Beach (UPVC Outlet Racing) 1min 57.094s
2. Charlie Atkins (Symcirrus Motorsport) +0.082s
3. Jack Smith (Woodland Kawasaki) +0.707s
4. Katie Hand (MH Solutions) +1.592s
5. Jamie Hanks-Elliott (FHO Racing) +1.604s