When comparing a brushed RC boat to a brushless RC boat where both are powered by a 3S LiPo battery, the differences in motor technology lead to vastly different experiences on the water, even though the voltage input is the same.
In terms of speed and power, a brushless motor is the clear winner. The mechanical limitations of a brushed motor restrict how fast it can spin, resulting in lower top speeds. A brushless motor, however, can take full advantage of the 3S voltage to spin much faster, delivering significantly higher speeds that make for a far more thrilling ride.
Efficiency and runtime also favor the brushless design. Brushed motors lose energy through the physical friction of their internal brushes rubbing against the commutator. This waste means you get shorter run times from the same battery. Brushless motors have no such friction, so they convert more of the battery’s power into actual movement, allowing you to run for longer periods before needing to recharge.
When it comes to durability and maintenance, the gap widens further. A brushed motor experiences constant mechanical wear; the brushes and commutator degrade with every run, meaning the motor has a limited lifespan and will eventually need maintenance or replacement. In contrast, a brushless motor has virtually no internal contact, making it inherently more durable and reliable. It requires little to no internal maintenance, though you still need to keep it clean and cool.
Cost is the one area where brushed motors hold a clear advantage. They are inexpensive to manufacture, so boats using them have a much lower initial purchase price. Brushless boats demand a premium because of their advanced electronics and superior materials.
Finally, their performance in and around water differs. Brushed motors have an open design that can eventually allow water to affect internal components, and they may struggle with torque in choppy conditions. Brushless systems, especially in modern boats, are often paired with water-cooling jackets for both the motor and speed controller, helping them manage the intense heat generated during high-speed runs and ensuring consistent, powerful output regardless of conditions.
Brushed:
Brushless: