Dublin City Council has said 6,000 people have subscribed to the Dublinbikes scheme which was introduced last weekend.
It said more than 5,000 people had registered for long-term hire cards and almost 1,000 for its 72-hour duration short-term subscriptions.
The council has 450 bicycles available from 40 stations between the Royal and the Grand canals.
Cyclists can register online for annual membership using a credit card at a cost of €10 or can pay with a credit card at 14 of the stations for a three-day €2 ticket.
Rental is then free for half an hour and costs 50 cent for the first hour, rising to €6.50 for four hours. The bikes are available from 5.30am to 12.30am.
The scheme is being funded by advertising agency JC Decaux in exchange for advertising space in the capital.