the arduino pins has a max A capacity of some mA 0.040A if I'm not wrong, if you try to put an supported consumer on the pin you risk to fry it, also check the voltages, check the specifications or datashit of the Arduino and for the motor, you need to check how much is the amperage consummation of the motor without load and under loa, also the voltages etc.... you could use a transistor for bigger current and higher V to use ... 2N3904 or 2N2222 is not bad I suppose or most commonly used, you'll need a common ground also from the arduino to close the circuits and activate the transistor .......