Richard Kerr and Alex Olsen swapped places at the top of the timesheets as Kerr went top by 0.146secs in FP2, with a best lap of 48.497secs.
As Olsen was forced to settle for second at the end of day one in Scotland, Dan Linfoot was third, just 0.047secs behind with Joe Talbot fourth and Lewis Rollo fifth.
Pirelli National Superstock with Santander Consumer Finance, free practice two:
1. Richard Kerr (AMD Motorsport) 48.497s
2. Alex Olsen (Cumins by Team IWR Honda) +0.146s
3. Dan Linfoot (Optimum Bikes Racing Ltd) +0.193s
4. Joe Talbot (JR Performance Racing) +0.428s
5. Lewis Rollo (IN Competition/Aprilia) +0.487s