Unbonding a rider

Can you unbond a rider and if so how?

bond the rider with another dragon or bond another rider with the dragon


That depends on what your asking. Do you want to just unbond or bond the rider to a different dragon? You can do both, simply bond the rider to a different dragon you have placed in your roster to put it on a different dragon, or bond a different rider to the same dragon to unbond and leave it without a dragon.