Let’s Talk about Torque
- Buck City Biker
- Jan 27, 2023
- 3 min read
Updated: Mar 29
Right then, torque, horsepower, kW… the usual spec sheet mess. It sounds tough, but we’ll keep it simple, and try to make the age-old argument between torque and horsepower a bit clearer, or maybe even irrelevant.
This matters even more when you’re looking at an electric bike, because EVs can deliver far more torque from a relatively low hp (horsepower) motor. That makes comparing them to an ICE (internal combustion engine) bike a bit tricky.
It’s not so much about ‘what’s the difference between torque and horsepower?’ you can go as deep as you like on that. What matters is how it translates to the ride. We’ll do this two ways. The complicated and accurate way, and the easy way. If you want the technical side, here it is, briefly.
The Complicated and Accurate Way
Horsepower is a measurement of the total power output of a system, e.g. your motorcycle motor. It can be calculated from torque, but includes a time element (rpm), which means the two aren’t directly comparable.
The calculation for BHP from torque is: BHP = torque X rpm / 5252.
Torque, on the other hand, is the turning force of the motor, the load it can apply to rotate. Think of it as the force at the axle that actually gets you moving.
The equation for torque is: Torque = Force × Radius (T = F × r). Torque is calculated differently to horsepower, which is why comparing them directly doesn’t always tell you much.
A Brief Note On kW:
Kilowatts (kW) are another way of measuring total power, similar to horsepower. The two are directly related (100hp = 74.57kW), but they’re used differently in practice.
On ICE bikes, horsepower is usually quoted as peak output, the maximum the engine can produce under ideal conditions.
On electric bikes, kilowatts are often quoted as continuous power, the level the motor can sustain over time. That’s why you’ll often see both continuous (rated) power and peak power listed. EV peak power can be compared directly to the horsepower of an ICE bike. They are both measured at maximum output.
The Easy Way (What Actually Matters)
HP is the overall capability of the motor. It takes into account both speed and torque. Higher hp generally means higher top speed and more overall performance, but it doesn’t tell you how that performance is delivered.
So torque is what you feel when you pull away. It’s the force at the rear axle or rear wheel. More torque means stronger initial acceleration and more immediate response when riding.
With torque and top speed information, you’ll get a much clearer idea of how the bike actually rides.
Where the Numbers Actually Matter
A high-torque electric bike will hit hard the second you open it up. No build-up, no waiting for revs, it just goes. That’s the shove you feel straight away. The kind that catches you out the first time if you’re not ready for it.
A high-horsepower bike, on the other hand, comes into its own as speed builds. It doesn’t always feel as aggressive off the line, but stay on it and it just keeps pulling. That’s where horsepower lives, not in the hit, but in what happens after. Different delivery. Different feel. Expressed in different ways.
The BCB Take
Always check the torque. It’s the difference between a bike that looks quick on paper and one that actually pins you back. It tells you how the bike will feel, how quickly it accelerates, and how it responds when you twist the throttle.
Then look at top speed alongside it. That combination gives you a much clearer picture of what you’re actually riding, not just what the spec sheet says. In simple terms: torque is how hard it pulls, horsepower (or kW) is how fast it can keep pulling. Top Speed is where you'll get to if you keep twisting.
We have our own calculation for torque: more torque = more fun.
Ride safe, folks
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