He pulls back suddenly, standing back up, almost like he'd suddenly become uncomfortable with the contact. It's not clear what part of what Shotlock said inspired this reaction.

"Mmmnn..."

Shotlock has a point, but he doesn't like this. Not at all. Optimus deliberates, then shakes his head.

"No, I am not risking any degree of spark pain for weaponry data. You go and get a scan, then if you get the all clear you do as much as you want."