Harlequins (21) 35 Tries: Dorn, Ellis, Jones-Bishop 2, Melling Goals: Orr 7 Drop Goal: Gale Bradford (6) 18 Tries: Whitehead, Sykes, Crossley Goals: Sykes 3
Ben Jones-Bishop's second try killed off any chance of a Bradford comeback
Harlequins stretched Bradford Bulls' winless run to eight games as they put their own worries behind them with a comprehensive win at The Stoop.
Luke Dorn, Andy Ellis and Ben Jones-Bishop blew the visitors away with three quick tries before the Bulls responded through Elliot Whitehead.
Paul Sykes's try started Bradford off in the second half but Bishop-Jones and Chris Melling answered back.
Steve Crossley added a late try for Bradford but it was little consolation.
An under-strength Harlequins appeared inspired against out-of-form Bradford, quickly going after the visitors to prompt early handling errors.
The visitors appeared unable to handle the pace of the Londoners, as Dorn and Ellis reaped the rewards with tries.
Full-back Dorn was then instrumental in Jones-Bishop's first try as he gathered Paul Sykes' kick and stepped on the gas before handing his team-mate a simple run-in.
There was a hint of a forward pass about Bradford's first try when Whitehead finished off some sharp footwork by Brett Kearney.
Orr made the Bulls pay with a penalty after Steve Menzies was pulled up for back chat and, as they appeared to fall apart, Gale added to their woes with a drop-goal on the half-time hooter.
Bradford pulled a score back through Sykes thanks to missed tackles but his side were still guilty of poor handling and even worse discipline.
Jones-Bishop added his second try and, when Menzies saw yellow, Orr stepped up to land the penalty.
Melling finished off a flowing move, after Orr had added another penalty before Crossley's late try gave the Bulls a glimpse of what might have been.
Harlequins assistant coach Latham Tawhai:
"When you look at the personnel we had missing to come up with a performance like that is huge.
"It says a lot about what we are doing as a club to produce that with just one overseas player.
"We have a lot of young kids out there playing. Results like that will give them that little bit of confidence.
"It is all about getting them some game-time under their belts and, if we can do that, the improvements will come.
Bradford Bulls coach Steve McNamara: "It was a very bad day at the office for us. We are a very frustrated side at the moment and we have to fix that.
"We gave away far too many penalties and that cost us. There were issues out there that we did not deal with properly.
"But we will not sulk about it - this is our job and we have to look at ourselves and not worry what is going on outside."
Harlequins: Dorn, O'Callaghan, Clubb, Jones-Bishop, Sharp, Orr, Gale, Ward, Ellis, McCarthy-Scarsbrook, Golden, Melling, Wilkes. Replacements: Bolger, Bryan, Mills, Krasniqi. Bradford: Kearney, Sheriffe, Platt, Nero, Halley, Addy, Sykes, Lynch, L'Estrange, Kopczak, Whitehead, Langley, Menzies. Replacements: Godwin, Hall, Crossley, Worrincy. Referee: Richard Silverwood (Dewsbury).