Running 3-6V motors with 7.2V
No. Why should it? You're operating outside the manufacturer's ratings so you can expect it to fail.







simulate this circuit &ndash; Schematic created using CircuitLab

Figure 1. Two-diode voltage dropper.

Wire two silicon diodes in series with the circuit. They will drop 0.6 to 0.8 V each and run the motor at about 5.8 V.