A balky horse; a balky client.
But the United States and its Allies ran into the same problem the Iranians have grappled with: the P-1 is a balky, badly designed machine.
The camera has an LED flash, which helps at close range at night, but the camera itself is balky and slow to focus and fire.
Whatever the demerits of microfilm as a storage medium (and it is notoriously balky, difficult stuff), at least it had a certain durability that the print article lacked.
As in many a human classroom, things get off to a balky start.
The balky horse refused the jump.