Rather than removing them entirely, I would look and see why they may be performing poorly. Is it because not enough people are searching for your keywords? If so, do some keyword research and perhaps take a slightly different spin. Is it because of poor layout? Does it have a lot of grammatical and spelling errors? All of these things will turn readers off and make them click off your hub or vote it down.
Go through, analyze the words you are targeting and see if there is enough potential for traffic. After that go through and correct any grammar/spelling errors and polish up your layout. Make sure your hubs are visually appealing and revise them to polish them up, but you shouldn't just remove them without trying to improve them first.