IIRC Robin would always perform a quick check before Batman would let up on the clutch. Something along the lines of “turbines to power, engines to speed”.
What exactly was the line?
According to the very useful Internet Movie Database (www.imdb.com) it’s
[about to zoom out of The Batcave!]
Robin: Atomic batteries to power. Turbines to speed.
Batman: Roger. Ready to move out.
And it was, as far as I know, the first show that had a clear and obvious safety message in showing B&R buckling up before rolling out. Frankly, the lack of seatbelt use in modern television is starting to annoy me, especially in simple-minded action shows that have a car crash every fifteen minutes.