Officer Stewart watches the listings and notes that many of the bikes are offered for far less than they're worth. That implies that the bikes are likely being sold by someone who knows nothing about bikes, but needs cash, fast.

"If you're an addict and you're dope sick, you'll be a person who needs the money immediately for your drug habit," said Stewart.

Thieves can also try their luck at used bike shops. In Portland, used bike stores have complicated paperwork that's supposed to prevent the buying and selling of stolen bikes. Most bike stores hold on to a bike for 15 days while they run its serial number through the police database of stolen bikes. If the bike comes up clean, the stores mail a check to the seller. If someone wants cash on the spot for a bike, they have to offer up a photo ID and be fingerprinted.

But the only trackable part of a bike is its frame. Bike parts, which can often be worth just as much, are completely untraceable. At used bike stores in town, cranks, stems and chainrings are piled high for browsing. Like socks and shoes bought at the Bins (aka the Goodwill Outlet), there's no telling where they came from.

Bikes that turn up ditched in shrubbery or left by the river with a serial number that doesnít have a match in police records go into a stolen bike limbo. They live for weeks or sometimes months in the vast police evidence warehouse in NW Portland, where hundreds of bikes of all makes, models and varying levels of cleanliness are stacked two high against the wall. Some bikes turn out to be evidence in crimes; some lucky ones are reunited with their owners.

But thousands every year are shipped off to the state surplus store in Salem, where they're sold in a state-run storefront or hawked on eBay alongside confiscated power tools, old typewriters and outdated bus stop shelters.

Out on the streets, Fast Lips is still missing. Crow printed up dozens of little flyers with photos of her bike, placing stacks in coffee shops and restaurants around Southeast Portland were Fast Lips was filched. Chances are, though, someoneís already using her wheelset and someone else is cranking her chain.