The short version: a geared hub motor uses internal planetary gears to spin a small, fast motor down to wheel speed, so it is roughly 50% lighter than an equivalent gearless motor, produces strong low-speed torque, and freewheels with almost no drag — but it cannot do regenerative braking and its plastic gears wear over time. A direct-drive hub motor bolts the wheel straight onto the motor with no gears at all, so it runs nearly silently, lasts almost forever, and can regen-brake — but it is heavier and always drags a little when you pedal it unpowered. For most everyday riders in Sydney, a geared rear hub — like the compact 250W unit on the Centauro e-bike — is the smarter daily pick, while direct-drive shines on fast, flat, high-mileage rides.
Both are “hub motors” — the motor lives inside the wheel rather than at the pedals. The difference is what happens inside that hub, and it changes the weight, the noise, the drag, and whether the motor can put charge back into your battery. Here is the plain-English engineering, straight from the workbench at Cyberbikes in Leichhardt.
Geared vs direct-drive hub motor: the quick-glance comparison
| Feature | Geared hub motor | Direct-drive hub motor |
|---|---|---|
| How it works | Small fast motor + internal planetary gears | Wheel bolted straight to the motor, no gears |
| Weight | ~50% lighter for the same power | Large and heavy |
| Low-speed torque | Higher (up to ~80 N·m on premium units) | Lower (~35 N·m typical) |
| Drag when unpowered | Freewheels — almost none | Always engaged — constant slight drag |
| Regenerative braking | No (freewheel blocks it) | Yes |
| Noise | Audible whir from the gears | Near-silent |
| Longevity | Gears wear over time | No moving parts but the wheel |
| Best for | Hills, stop-start commuting, light weight | Flat, fast, high-mileage, quiet riding |
How does a geared hub motor actually work?
A geared hub motor puts a small, high-speed electric motor and a set of planetary reduction gears inside the wheel hub. Electric motors are most efficient and powerful when they spin fast, but a bike wheel only turns at around 200 rpm at road speed. According to Grin Technologies (ebikes.ca), the motor inside a geared hub is often spinning above 3,000 rpm, and the gears reduce that down to wheel speed. That gearing is why a small motor can punch above its size.
Two things fall out of that design. First, ebikes.ca notes these motors typically weigh about 50% less than an equally powerful gearless motor, and they often produce superior torque — a premium geared hub like the German Heinzmann can make up to 80 newton-metres, versus about 35 N·m for a typical direct-drive machine. That extra low-speed twist is exactly what you want pulling away from lights on Parramatta Road or grinding up a hill.
Second, almost every geared hub has a freewheel inside — the same one-way clutch idea as a normal bike cassette. When you are pedalling without power, the wheel spins freely and the motor stays still, so there is very little rolling friction. The trade-off, as ebikes.ca points out, is that this freewheel makes regenerative braking impossible: the motor is mechanically disconnected the moment you stop driving it. Geared hubs are also generally more expensive, have more moving parts prone to wear, and produce an audible whir under load.
Want to see one opened up? Our Cyberbikes workshop video below walks through exactly what is inside a geared hub and what to look for when buying one.
How does a direct-drive hub motor work?
A direct-drive (or “gearless”) hub motor is about as simple as machinery gets. As ebikes.ca describes it, you take an electric motor, hold the axle still, and let the body of the motor spin — then lace a bicycle rim straight onto that spinning body. There are no moving parts other than the wheel itself. It is almost always a radial-flux brushless DC motor with permanent magnets around the inside of the hub and the windings fixed to the axle.
Because the wheel turns slowly (~200 rpm) and the motor has no gears to multiply its speed, a direct-drive hub has to be physically large and heavy to make decent power and torque. In exchange, you get two things a geared hub cannot match. It is near-silent, and because the motor is always mechanically engaged, it can do regenerative braking — feeding some energy back into the battery when you slow down.
That “always engaged” nature is also the catch. You are permanently overcoming the motor’s cogging and drag torque, even when you are not using it. ebikes.ca measures this drag at roughly 0.3 to 1 newton-metre, and it increases with speed — enough that a poorly made one can feel, in their words, like you are always riding with a soft tyre. With no gears to wear out, though, a good direct-drive hub can outlast the rest of the bike.
Is a watt a watt? What “250W” really tells you
Here is the part that trips up most buyers. A motor’s wattage does not tell you which type it is, and it does not even mean what most people think. As ebikes.ca puts it bluntly, 600 watts of mechanical power makes a bike behave the same whether it comes from a small geared hub, a massive direct-drive hub, a mid-drive, or a giant gust of tailwind. A watt is a watt. What changes between motor types is how that power is delivered, how much the motor weighs, and how it feels.
Two bits of real physics help here. Power = torque × rpm (in SI units, watts = torque in N·m × rotational speed in rad/s). That is why a geared hub’s high internal rpm lets a small motor make useful power. And it is torque, not power, that overheats a motor: doubling the current to double the torque quadruples the heat in the copper windings (the I²R relationship). This is why a compact geared hub, which multiplies torque mechanically, can climb without cooking itself, while a direct-drive hub leans on sheer size to stay cool. If you want the full breakdown of the numbers, our guide on how an e-bike motor controller works and what the amps mean goes deeper.
Which hub motor is right for Sydney riding?
For the everyday Sydney commuter — bike paths, shared paths, stop-start traffic, a few hills — a geared rear hub is usually the better fit. It is lighter, gives you more low-speed torque for pulling away and climbing, and freewheels efficiently so unpowered pedalling feels natural. That is why the Centauro e-bike from Cyberbikes uses a compact 250W rear hub motor, paired with a 48V 25Ah (1,200Wh) Samsung battery. Read the current Centauro specifications on our product page to see the full build.
Direct-drive makes more sense if you ride long, fast, flat distances, want the quietest possible motor, or specifically want regenerative braking on big descents. For a full rundown of how motors, sensors, and controllers fit together across both mid-drive and hub systems, see our companion guide on how e-bike motors actually work.
Whichever you choose, the law is the same. Under NSW rules, a road-legal pedal-assist e-bike is limited to 250W continuous power and cuts assistance at 25 km/h (a throttle-only mode is capped at 6 km/h). The Centauro is built to meet EN 15194 for exactly those power and speed limits, so your choice of geared or direct-drive does not change what you are allowed to ride.
Frequently Asked Questions
Which is better, a geared or direct-drive hub motor?
For most everyday and hilly riding, a geared hub motor is better because it is about 50% lighter, has more low-speed torque, and freewheels with almost no drag. A direct-drive hub motor is better for fast, flat, high-mileage riding where near-silent running and regenerative braking matter more than weight.
Can a geared hub motor do regenerative braking?
No. Almost every geared hub motor has a freewheel inside that mechanically disconnects the motor from the wheel when you are not driving it. That freewheel makes regenerative braking impossible. Only direct-drive hub motors, which are always mechanically engaged, can feed energy back into the battery.
Why are direct-drive hub motors so heavy?
A bike wheel only turns at around 200 rpm, and a gearless motor has no gears to multiply its speed. Electric motors make power in proportion to how fast the magnets and windings move past each other, so a direct-drive hub has to be physically large and heavy to produce useful power and torque at that low wheel speed.
Does the Cyberbikes Centauro use a geared or direct-drive hub motor?
The Centauro uses a compact 250W rear hub motor tuned for everyday commuting and cargo carrying in Sydney, paired with a 48V 25Ah Samsung battery. Compact, lightweight 250W commuter hubs of this type are typically geared designs. Pop into Cyberbikes in Leichhardt for a test ride to feel it for yourself.
Test-ride the difference at Cyberbikes
The best way to understand a hub motor is to feel one under you. Come in for a test ride at Cyberbikes, 281 Parramatta Road, Leichhardt, browse the Centauro e-bike online, or call us on 0491 794 668 (Tuesday–Saturday). Ask about our rent-to-own plans from $99.99/week.
Technical references: Grin Technologies / ebikes.ca (Hub Motors and Futility of Motor Power Ratings).
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