Kulcsar limped off with knee and ankle injuries after a 50-50 challenge by Nigel Pepper - the sort he was bought to win - but Rangers still managed to take the points.
Harford is looking for an aggressive approach from his midfield and Kulcsar, a regular with Bradford until just eight days ago, was signed last week to provide it.
"I want to see a much better reaction when we lose the ball," Harford said. "I want to see a much more aggressive approach to winning it back and I think there was some improvement in that direction today."
If Harford's luck was out with Kulcsar, he was blessed when John Spencer made the most of a reckless challenge inside the penalty area by Bradford full-back Chris Wilder.
Gavin Peacock shot home the 28th minute penalty - his ninth goal of the season - to earn Rangers only their second win in 10 games and leave them nine points adrift of the play-off places.
The Bradford manager, Chris Kamara, said: "We can't really have too many complaints about the penalty. Spencer pushed the ball wide of Wilder and then went down. What upset me was that it followed a corner to us."
Goal: Peacock pen (27) 1-0.
Queen's Park Rangers: Roberts; Yates, Brevett, Kulcsar (Murray, 25), Ready, Maddix, Spencer, Peacock, Quashie, Sheron (Gallen, 76), Sinclair. Substitutes not used: Perry.
Bradford City: Walsh; Wilder, Small, Murray, Youds, O'Brien, Lawrence (Blake, 67), Pepper, Steiner (Edhino, 50), McGinlay (Ramage, 67), Beagrie.
Referee: S W Mathieson (Stockport).
Bookings: QPR: Sheron. Bradford: O'Brien.
Man of the match: Walsh.
Attendance: 8,853.Reuse content