Should I sell my mountain bike for money?
Haha well depends because, Do you mountain bike? other questions also are is it a DownHill Bike or All Terrain, What kind of bike? Usually if its not a DownHill Bike then its not really worth it to resell it.
For what else are you willing to sell your bike ???
If you dont really need money than you can have an exchange for another bike or update the model that you allready have.