The essentials in 30 seconds
- A bow thruster holds position and moves the boat slowly using GPS anchoring. It does not replace an outboard for underway sailing.
- Thrust: the Minn Kota published rule calls for 2 pounds of thrust per 100 pounds of loaded boat weight. In kilograms: 2 kg per 100 kg.
- Voltage: Garmin Force Kraken and Force Pro, and Lowrance Ghost X operate on 24 or 36 V. None accept 12 V.
- Shaft length: measure from the deck to the waterline, with the boat loaded. Garmin adds 20 cm if you fish often in waves.
- Battery, circuit breaker, and cables are not included. Skysat has not installed any of these thrusters: everything comes from the manufacturers’ manuals.
Table of contents
- What a bow thruster is for
- How much thrust for your boat?
- 12, 24 or 36 V: what voltage changes
- What shaft length?
- GPS anchoring, course keeping, route tracking
- Installation, controls, and integrated transducer
- What’s not in the box
- Limitations and pitfalls
- Our verdict by program
What a bow thruster is for, and what it is not for
An electric bow motor, called a « trolling motor » in the manuals, bolts to the deck at the bow. Garmin requires it for its Force Kraken and Force Pro models. It operates once on site: running a break at a steady speed, repositioning silently, holding the boat on station.
It is not a backup outboard. Garmin does not present the Kraken or the Pro as a primary propulsion system; the thermal engine handles the passage.
How much thrust for your boat?
Thrust is measured in pounds (lb); 100 lb is about 45 kg. This is the force the propeller exerts on a test bench, not a speed.
The only quantified rule we found in a manufacturer’s documentation is from the Minn Kota selection guide; Garmin does not publish an equivalent in the manuals we have read. You need at least 2 pounds of thrust for every 100 pounds of loaded boat, including crew, fuel, and gear. In kilograms: 2 kg for every 100 kg. Minn Kota recommends extra margin if wind or current are significant in your areas.
| Loaded boat weight | Maximum length | Minimum thrust | Voltage |
|---|---|---|---|
| 1 500 lb (680 kg) or less | 14 ft (4.3 m) | 30 lb | 12 V |
| 2 000 lb (907 kg) | 17 to 18 ft (5.2 to 5.5 m) | 40 to 45 lb | 12 V |
| 2 500 lb (1 134 kg) | 20 to 21 ft (6.1 to 6.4 m) | 50 to 55 lb | 12 V |
| 3 000 to 3 500 lb (1 361 to 1 588 kg) | 23 ft (7 m) | 70 lb | 24 V |
| 4 000 lb (1 814 kg) | 25 ft (7.6 m) | 80 lb | 24 V |
| 4 500 lb (2 041 kg) and above | over 25 ft | 101 to 112 lb | 36 V |
Minn Kota selection guide, revision dated August 21, 2020; conversions by Skysat. This table helps size thrust; shaft length and intended use also factor into model selection.
Sample calculation, not a real boat: a 6 m open boat weighs 1,500 kg loaded, or 3,300 lb. The rule calls for 66 lb; the table classifies it as 24 V with 70 lb. A Force Kraken or a Force Pro delivers 80 lb at 24 V and 100 lb at 36 V per Garmin: both are suitable.
12, 24 or 36 V: what voltage changes
Voltage is that of the battery bank, and it is the motor that dictates it. Minn Kota summarizes the logic: one 12 V battery per 12 V segment.
On a dual-voltage motor, the same unit delivers more thrust at 36 V than at 24 V, with a similar maximum current. Garmin quotes 2,160 W at full power under 36 V, for 60 A at both voltages.
| Motor | Voltage | Claimed thrust | Continuous current | Water |
|---|---|---|---|---|
| Garmin Force Current (transom, kayak) | 12 or 24 V | 30 lb (12 V), 50 lb (24 V) | 40 A | fresh, brackish, salt |
| Garmin Force Pro 50" and 57" | 24 or 36 V | 80 lb (24 V), 100 lb (36 V) | 60 A | fresh, brackish, salt |
| Garmin Force Kraken 48" to 110" | 24 or 36 V | 80 lb (24 V), 100 lb (36 V) | 60 A | fresh, brackish, salt |
| Lowrance Ghost X 47" | 24 or 36 V | « 20 % more than the original Ghost »; no published pound value | not published; 50 A breaker (manual series Ghost) | fresh ("freshwater" model) |
Sources at the end of the article, consulted on September 30, 2026; Garmin data per ISO 13342.
Battery chemistry, capacity, charger and protection are covered in a separate guide.
What shaft length?
Too short, the shaft causes the propeller to ventilate as soon as the boat pitches; too long, it complicates stowage. Manufacturers start from the same measurement: the height between the mounting surface and the waterline.
Garmin asks you to measure from the deck, at the location of the bracket, down to the water. Add 8 inches (20 cm) if you frequently encounter waves; between two lengths, choose the longer one. Minn Kota adds 5 inches (13 cm) in choppy water and requires the motor block to be 12 inches (30 cm) below the surface.
Minn Kota reference heights for bow mount: 22 to 28 in (56–71 cm), shaft 48 to 52 in (122–132 cm). Height 28 to 44 in (71–112 cm), shaft 54 to 72 in (137–183 cm). Above 45 in (114 cm), shaft 87 in (221 cm).
Catalogue lengths: Force Pro in 50" (127 cm) and 57" (144 cm). Force Kraken in 48", 63", 75", 90" and 110", i.e. 122 to 279 cm; the 90" and 110" models ship with a stabilizer. Ghost X in 47" (119 cm).
Measure your boat afloat and loaded. On the trailer, the bow sits higher than when fishing. Send us the measurement and a photo of the bow: we verify the length before ordering.
GPS anchoring, heading hold, route tracking
GPS anchoring, called “anchor lock” by Garmin, uses the motor’s GPS to hold position. The motor pivots and pushes on its own to stay on station. You shift this point from the remote, forward, aft, port or starboard.
Heading hold keeps a compass heading and corrects leeway. Speed control holds a speed over the ground. Route tracking strings together waypoints synchronized with a compatible Garmin chartplotter. Lowrance describes the same functions on the Ghost X.
Garmin manual excerpt. Calibrate the compass before first use. The autopilot does not relieve you of conning: expect sudden stops and sharp turns, and train in open, calm water.
Mounting, controls and integrated transducer
| Criteria | Force Kraken | Force Pro | Ghost X |
|---|---|---|---|
| Mount | tilting, for high freeboards and cluttered bows | scissor-type, two gas struts | scissor-type, double-acting gas struts |
| Supplied controls | remote control; wireless foot pedal sold separately | wireless foot pedal and remote control | wired foot pedal; GPS remote control optional |
| Integrated transducer | GT56UHD-TR on black versions 48", 63" and 75" only | GT56UHD-TR on 50" and 57" | Active Imaging 3-in-1 in the cone |
| Salt water | yes; rinse with fresh water after each use | yes; same instruction | no: freshwater model |
The Kraken accepts an optional LiveScope mount; its manual is on the product page. At Skysat, the Ghost X is only offered as a service unit without a mount, with the Ghost series parts. The complete motor is not online: request a quotation.
What is not included
- The battery. None of these motors include one. For a Force Pro or a Kraken, Garmin requires a 24 V or 36 V bank capable of supplying 60 A continuously. Example for 24 V: the Rebelcell 24V75 EDGE, rated for 100 A.
- The circuit breaker. Garmin requires 60 A continuous, rated for 42 V DC or more, not supplied. The Blue Sea 285 series 60 A is rated for 48 V and ignition-protected (SAE J1171). The Ghost series manual recommends 50 A.
- The extension cable. The Kraken cable is 1.2 m long. Garmin requires at least 75 °C single-conductor flexible cable. Recommended cross-sections: 16 mm² up to 3 m, 25 mm² up to 4.6 m, 35 mm² up to 9.1 m.
- Other items. 60 A deck plug (optional), Kraken foot pedal, Kraken stabilizer for 48" to 75" models, AA batteries for the remote control.
- The deck. It must support the weight (22.6 to 26.2 kg for a Kraken) and loads, with a backing plate if needed.
Limits and pitfalls
- Thrust is not speed. 100 lb hold a boat head-to-wind; they do not make it plane.
- No 12 V in Garmin at the bow. The Kraken and the Pro accept 20 to 45 V DC. For a lightweight dinghy on 12 V, you need another brand, which Skysat does not yet sell.
- Battery gauge. Garmin defaults to lead-acid. With lithium, set the battery type in the Battery Setup menu, otherwise the display is misleading.
- Waterproofing by subassembly. The Kraken manual gives IPX5 for the shaft housing, IPX7 for the steering and display, IPX8 for the propeller unit.
- Commercial vs. measured thrust. Garmin claims 100 lb at 36 V (ISO 13342); its manual measures 114.7 lb at 38.4 V, the voltage of a charged lithium bank. Compare figures obtained the same way.
- Skysat has not yet installed any Force or Ghost. Everything above comes from Garmin, Lowrance and Minn Kota manuals.
Our verdict by program
- Open 5 to 7 m offshore, high freeboard. A Force Kraken, in 63" or 75" depending on your measurement, in 36 V if wind is your norm.
- Bass boat or dinghy in freshwater, flat deck, foot pedal. A Force Pro 50" or 57", supplied with foot pedal and remote. With a Lowrance screen, the Ghost X is the equivalent; ask us.
- Kayak. The Force Current, transom-mount electric motor in 12 or 24 V; its spec sheet details its use case.
- Lightweight dinghy under 700 kg laden, 12 V budget. No Garmin bow motor fits, and 12 V motors from other brands are not yet at Skysat. We prefer to tell you up front.
- You mainly want to cruise quietly. Dinghy, dinghy sailboat, sailboat: an electric outboard, not a bow thruster.
Sources
- Garmin: Force Kraken manual (v7, 11/2025), Force Kraken installation guide (v10, 01/2026), Force Pro manual (v3, 08/2026), Force Current manual (v3, 07/2026), support FAQ on shaft length.
- Minn Kota: Motor Selection Guide (revision 21/08/2020).
- Lowrance: page Ghost X 47", launch press release, installation manual for Ghost series (988-12451-005, 2020) on the Skysat sheet.
- Blue Sea Systems and Rebelcell: Skysat sheets for the 285 series 60 A circuit breaker and the 24V75 EDGE battery.
Disclosure: Skysat sells Garmin, Lowrance, Simrad, Rebelcell, Blue Sea Systems and Minn Kota products. MotorGuide is not yet in the catalog. This article is not sponsored and was not reviewed by the brands mentioned.
