Ash Barnes set the pace as the championship made its first appearance in Scotland this morning, holding off Aaron Silvester with a best lap of 57.561secs.
Barnes and Silvester were the only two riders to dip below the 58sec window in the wet conditions.
Third quickest was Rossi Banham, with Zak Shelton fourth and Rhys Stephenson fifth.
Pirelli National Sportbike with Moneybarn Vehicle Finance, Free Practice 1:
1. Ash Barnes (Raceways Yamaha)
2. Aaron Silvester (MIH Solutions/Macadam Racing) +0.174s
3. Rossi Banham (RB Racing) +1.032s
4. Zak Shelton (XMT Racing) +1.069s
5. Rhys Stephenson (Rocket Racing) +2.125s