Burricleta.cat is in Cassà de la Selva, they are very close to Villa CP. This is a great place to rent electric bikes and ride the old train track that used to go from Girona down to the beach at Sant Feliu de Guixols (about an hour each way from Cassà de la Selva).
Burricleta also has a shop in the centre of Girona, in the old town, which can be a fun way to explore the city.
Ebici http://www.ebici.cat/english/rent/ is in the centre of Girona. They have various styles of bikes, including great looking mountain bikes. Rent by the hour or the day. They are also near the beach in Platja d’Aro, which is perhaps more convenient for a day cycling at the coast.
Happy Bikes are in the village of Madremanya, about 15 mins from Villa CP by car: http://www.happybikesgirona.com.