shop fly
A person, who habitually hangs out at bike shops. For no good reason, other than to talk "shop". Often unemployed, broke, and without a life of their own, they take up the majority of your time, without spending any money.
"I had three projects on the go, but I couldn't get anything done with the shop fly buzzing around all the time. He's always asking stupid, fucking questions, while I'm trying to finish a project."