Dart's right about the Bike thing - sell it in the US, travel light and put the cash towards buying one here. A lot of expats in Spain are moving back to their own countries because of the economy and are selling their stuff so you should be able to pick up a bargain.
Whether you are coming to Spain to study or to look for work one of your very first priorities should be obtaining an NIE Number. Without this you will find it almost impossible to do most essential things like open a Bank Account. Here is a link attached explaining the procedure - http://www.tumbit.com/how-to-guides/articles/27-nie-number.html