Valencia runs a free bike sharing scheme – Valenbisi (a play of words based on ‘Valencia’ with ‘Bici’ (bike) and Si’ (yes) ) which allows you to pick up a bike at any of the locked stations and return it another station (it doesn’t have to be the same one).
To use the system, you need a card – which you can order here. The downside is that you need to order your card upto 21 days in advance or have a metro card. So, it is best to be organised and think ahead.
If time is not on your side, then you can still use one of the bike hire companies like Valencia Bike Rent.