What motor sizes actually mean on an electric skateboard

When you are researching electric skateboards, motor specifications show up in every product description. Numbers like 6374 and 6368 get listed alongside wattage figures and top speeds, and most articles treat them as self-explanatory. They are not. Understanding what these dimensions actually mean changes how you evaluate a board, especially if you are deciding between setups and want to know whether the hardware matches your terrain.

The number is a physical measurement, not a rating

The four-digit motor code describes the physical dimensions of the motor can, which is the cylindrical housing that contains the stator and windings. The first two digits are the diameter in millimetres. The second two are the length. So a 6374 motor is 63mm wide and 74mm long. A 6368 is the same diameter but 6mm shorter.

That is it. The number does not directly tell you the wattage, the torque output or the efficiency. What it tells you is the size of the motor, and from that you can draw reasonable conclusions about what it is capable of.

A longer motor can accommodate more copper windings inside the stator. More windings means greater magnetic flux, which translates to higher torque at lower RPM. This is why the 6374 is generally found on boards designed for demanding terrain and heavier loads, while the 6368 suits setups where weight and compactness matter alongside solid performance.

Why the difference matters on real terrain

On a flat sealed road, the distinction between these two motor sizes is not something most riders will feel in a meaningful way. Both configurations, when paired with capable controllers and proper gearing, will accelerate you confidently and hold speed without strain.

The difference becomes real when you add variables: a steep climb, a heavily loaded rider, all-terrain tyres creating rolling resistance, or sustained uphill runs that ask the motors to work hard for extended periods. In these conditions, a longer motor with more thermal mass and greater torque capacity holds its composure better. It heats up more slowly, maintains torque more consistently and recovers faster.

New Zealand's geography makes this relevant in a direct way. Wellington's suburb gradients are genuinely steep. Queenstown's trails are variable and demanding. Even commuting in Auckland or Christchurch often involves undulating terrain that would be considered aggressive in flatter parts of the world. A motor that handles heat and load well is not a luxury consideration here. It is a practical one.

Where wattage fits into this picture

Motor size and rated wattage are related but not the same thing. The 6374 motors on the Diablo Bamboo are rated at 3500W each, giving a combined output of 7000W. The 6368 motors on the Fusion are rated at 3000W each, totalling 6000W. The extra length of the 6374 supports that higher rating because there is simply more material inside to generate and sustain that output without excessive heat.

This matters most at the extremes. Under gentle riding conditions, neither motor is being pushed. At the limit, whether that means a sustained 45 per cent gradient, a heavier rider or riding in sport mode on rough trails, the 6374 has more headroom before it starts to throttle back to protect itself.

The EFOC 2.0 controller on the Diablo handles up to 200A, which gives the motors the current they need to perform at the top end of their capability. The system is matched to the hardware, and that matching matters as much as any individual specification.

The Diablo Bamboo All-Terrain as the practical case study

The Diablo Bamboo All-Terrain uses dual 6374 motors, and the reasoning is straightforward. This is a board designed to handle grass, gravel, dirt and sealed surfaces on 175mm pneumatic tyres. All-terrain riding introduces rolling resistance that street riding simply does not, and the drivetrain needs to compensate for that without falling flat on climbs or getting sluggish under load.

The 864Wh Samsung 50S battery supports up to 50 km of real-world range on the all-terrain setup, and the 7000W motor system means that range is not being compromised by motors struggling to do their job. The board handles gradients beyond 45 per cent, which puts it well above what the Fusion's 35 per cent rating covers. At 15.3 kg, it carries the additional mass of the all-terrain wheel setup without the drivetrain feeling overworked.

The bamboo deck adds a layer of natural flex that works in favour of the rider on uneven surfaces. It absorbs small impacts and road imperfections, which matters more on dirt and gravel than it does on smooth asphalt. The 6374 motors underneath are doing the heavy work while the deck is doing the comfort work. Both elements are chosen for the same purpose.

Choosing by what the terrain actually asks of the motor

If your riding is mostly flat urban commuting on sealed surfaces, the 6368 motor in a Fusion Street will serve you well and the lighter overall package becomes an advantage. The 6374 is not the right answer for every rider.

But if you are riding anywhere with real hills, mixed surfaces or consistent off-road use, the larger motor gives you performance that holds up over time. Hamilton's river trails, the gravel tracks outside Christchurch, the waterfront paths in Wellington that suddenly pitch upward, these environments ask more of a drivetrain than a city grid does. The 6374 is built to answer that without compromise.

There is also a durability argument. A motor running within its thermal comfort zone for most of its life will last longer and perform more consistently than a smaller motor working near its limit. Choosing hardware with genuine headroom is not about extracting the maximum every session. It is about having a board that still performs well a few years from now.

The number on the motor is a physical description. What it describes is a machine with more capacity, more thermal resilience and more torque where it counts. For most serious all-terrain riding in New Zealand, that is exactly what the terrain demands.