Aside from the obvious dangers of cycling on city streets, renting an aqua-colored bike from a street stand seems innocuous enough.

But Biki users beware. Paying $3.50 to rent a bike could end up in a $1,200 charge.

Since BikeShare Hawaii’s launch in June, the program’s operator has attempted to charge 107 customers a $1,200 “lost or stolen” bike fee, despite saying that improper docking of the bike is the usual culprit. Biki says its bicycles cost roughly $1,200 each.

A 35-year-old Waikiki woman, who was a regular Biki monthly pass-holder and frequent user, said Biki charged her $1,200 on her debit card in November, wiping out her bank account. She was charged after the bike had been missing for 24 hours. Within a few days the bike was returned, and the woman’s money was restored to her account.

While Biki has attempted to charge 107 customers for the full value of the bicycle, fewer than 10 have actually paid the fee, the company said.

“Out of this number (107), some have been waived because the bike was returned,” said Kelvin Tjia, CEO of Secure Bike Share, which operates Biki, in an email.

“The number of lost or stolen charges that have been processed is less than 10,” he said.

Some charges failed because of credit card issues or lack of funds. Others remain in dispute with credit card companies. In other cases Biki does not have the renter’s contact information.

BikeShare Hawaii CEO Lori McCarney said with certainty the 35-year-old Waikiki woman, who asked not to be identified further, improperly docked the bike, and the customer is held responsible, regardless of whether the bike is lost, stolen or improperly docked.

“We have seen this to be an issue, not docking the bike properly,” she said. “If they wait for the green light, they’re in good shape.”

Bicycles are kept at the Biki docking stations in a rack with an electronic lock. When renting a bicycle, a customer pays a fee and gets a code to unlock the bike.

When returning the bicycle, the customer must push the front wheel firmly into the rack and wait for a green light, indicating the bike has been locked.

McCarney discounted a possible problem with the system in the case of the Waikiki woman, saying the stations are checked once every one or two days.

The company called to inform the woman that her bike had been missing for 24 hours and was officially considered lost, which is when the company charges the renter. Because the woman used her debit card for a recurring $15 monthly charge, Biki debited her account $1,200.

To prevent improper docking, Biki began text messaging months ago when the bike is successfully docked, which is also signaled by the green light.

Tjia said the incidence of lost and stolen bikes is low. Biki averages 2,008 rides per day and had about 550,000 rides between launching on June 28 and March 19, the company said.

Tjia said the lost-bike fee is assessed “to discourage people from stealing a bike (or leaving it somewhere it may be stolen) and to compensate for our financial loss if a bike disappears.”