City officials announced on Friday they will add 2,000 more Bixi rental bikes in five new neighbourhoods across Montreal. (CBC)

The City of Montreal announced Friday it’s expanding the Bixi bike-rental program several months earlier than expected.

By the end of the summer, the city plans to have 100 new bike stations and about 2,000 new communal bikes available to people in five new neighbourhoods, including Park Extension, Mercier/Hochelaga-Maisonneuve, and parts of Côte-des-Neiges/Notre-Dame-de-Grâce.

This will bring the total number of Bixi bikes to 5,000, spread out over 400 stations across the city. These new additions bring the overall price tag of the program to $23 million, but city officials said it is on track to pay for itself within three years.

So far, rental stations have been concentrated in the plateau, downtown, and the western part of Rosemont.

"It's really a huge success. People are using it, they are very proud of it," said André Lavallée, executive committee member responsible for transportation in Montreal. He said he’s encouraged by apartment rental ads he’s seen in the newspaper that list their proximity to a Bixi station as a selling feature.

Lavallée said since the Quebec-built bikes first appeared in the city in May, Montrealers have logged more than a million kilometres on Bixis. By the end of the season, he said Montreal would have more shared bikes than any other city except Paris.

Lavallée also confirmed the city is working to fix a few design problems with the locking mechanisms at Bixi stations. A number of bikes have disappeared, or been vandalized since they were introduced.