Harbor Freight RC Boat: The Neptune Speedboat, Specs and Upgrades
The Harbor Freight RC boat most people mean is the Neptune RC Speedboat (item #95641), a budget twin-motor boat sold for around $35–50. It has a 27 × 9 inch hull, twin 380 brushed motors, a 7.2 V NiMH battery, digital proportional control with six frequency options for racing several boats, and a stated top speed of 20 mph (owners often report 15–18 mph) with about 120 m of control range. It’s no longer a current product, so most are found used.

Neptune specs
| Item | Value |
|---|---|
| Item number | 95641 |
| Size | 27 × 9 in (about 69 × 23 cm) |
| Motors | Twin 380 brushed |
| Battery | 7.2 V NiMH |
| Speed | Up to 20 mph claimed; about 15–18 mph reported |
| Range | About 120 m |
| Frequencies | Six, for racing several boats |
From the original listing and owner reports.
Buying one used
Because it’s no longer sold new, check used Neptunes carefully. The weak points are the hull seal, corroded battery contacts and motor wiring, and worn shaft bushings. Ask whether the battery and charger are included, since old NiMH packs may be dead. Test the boat in a bathtub before paying if you can: motors, steering and the transmitter should all work, and no water should get inside after a few minutes. A boat in its original box with the manual is worth more.
Common fixes
- Water inside: re-seal the hatch with fresh tape or foam gasket; grease the shaft tubes.
- Weak or no motor: clean corroded contacts, replace tired 380 motors (standard size).
- Short run time: replace the NiMH pack with a new one of the same voltage and connector.
- Poor steering: check the rudder linkage and servo.
- Short range: fresh transmitter batteries, straighten the antenna.
Upgrades
Owners upgrade with fresh NiMH packs, better props, and sometimes a 2S LiPo with care (checking the electronics can handle it and adding a low-voltage alarm, since the original ESC has no LiPo cutoff). Brushless conversions are possible but need a new ESC, water cooling and often a new drive line, which usually costs more than buying a modern brushless boat. For current budget boats, see cheap and fast RC boats.
Running tips
- Charge the battery fully; NiMH packs like a full charge before use.
- Check the hatch is sealed before every run.
- Run on calm water near the shore.
- Stop when the boat slows; let the motors cool.
- Dry the boat inside after each session.
Neptune vs modern budget boats
Today’s budget boats often have brushless motors, LiPo batteries, water cooling and self-righting for similar money, so they’re faster and more practical. The Neptune’s appeal now is nostalgia, simplicity and very low prices on the used market. For lake running, compare options in best RC boat for a lake.
Used Neptune checklist
- Transmitter and boat on the same frequency.
- Battery and charger included and working.
- No cracks in the hull.
- Both motors spin; rudder moves both ways.
- No corrosion in the battery compartment.
Why it was popular
The Neptune arrived when cheap RC boats were mostly small and slow. A 27-inch twin-motor boat at a tool-shop price was a lot of boat for the money, and it was easy to buy alongside other shopping. Many people bought one as a first RC boat or a gift, and some went on to modify them as a cheap way into the hobby. Forums still have threads from owners swapping motors, adding cooling and changing propellers, which is a useful resource if you buy one used today.
FAQ
How fast is the Harbor Freight RC boat?
Rated 20 mph; owners report about 15–18 mph.
Does Harbor Freight still sell RC boats?
The Neptune is discontinued; most are bought used.
What battery does the Neptune use?
A 7.2 V NiMH pack.
Can several Neptunes run together?
Yes, on different frequencies.
More on this topic: the complete RC Boats guide covers the basics behind this article.




