Understanding the Hidden Tax of Gravel Riding

The Gravel Multiplier: Why It Costs More

First, accept that the numbers on your computer are lying to you. Off-road riding exacts a physical toll that raw power data doesn't always capture.

The Vibration Tax

On smooth tarmac, your bike glides. On gravel, it vibrates constantly. Your core, shoulders, and stabilising muscles have to micro-contract thousands of times an hour to absorb this chatter. You are essentially doing a three-hour plank while trying to pedal. This burns energy that doesn't go into the pedals.

The Death of Inertia

On the road, you pedal hard and glide for twenty metres. On the majority of gravel, inertia dies the moment you stop pedalling. There are no "micro-recoveries." The load on your muscles is relentless, draining your glycogen stores much faster than the "on/off" rhythm of road riding.

The Data

I see this in client files and feel it in my own legs whilst riding. For the same 200 watts, heart rate is often 5-10 bpm higher on gravel than on the road. This represents a significant drop in Gross Mechanical Efficiency. Your body is burning more oxygen just to stabilise the chassis, meaning you pay a higher physiological price for the same power output. Respect the multiplier and fuel for a ride that is 30% harder than the distance suggests.

The Torque Trap: Smoothness vs. Power

The most common mistake road riders make on dirt is gear selection. When the terrain gets steep and loose, the instinct is to slow the cadence and grind a bigger gear to feel "in control." On loose climbs, high torque is your enemy.

The Slip

Grinding a heavy gear puts massive spikes of power into the rear tyre on every down-stroke. On loose gravel, this breaks traction. The wheel spins, you lose momentum, and you stop.

The Fix

You need to ride like a mountain biker. Select a lighter gear that allows you to stay seated (keeping weight on the rear wheel) and pedal in smooth circles. It isn't about spinning wildly; it is about applying constant, even pressure throughout the entire pedal stroke to keep the tyre fixed to that loose stuff.

Braking Bad: The Rear Rudder

Descending on gravel is where the panic sets in. On loose surfaces, grabbing the front brake at the wrong moment is the fastest way to hit the deck. To stay upright, you must separate your braking forces:

The Front Brake (The Anchor)

This provides 70% of your stopping power, but it must be used in a straight line. Shed your speed before the corner while the bike is upright.

The Rear Brake (The Rudder)

Once you tip the bike into the corner, the front brake is dead to you. If you need to tighten your line or scrub speed mid-turn, gently drag the rear brake. It acts like a rudder, pulling you into the apex without risking a front-wheel washout.

The Universal Fix: Tyre Pressure

Finally, none of the above matters if your setup is wrong. Coming from the road, the instinct is to pump tyres up hard to make them "fast." On gravel, this is dead wrong.

The Physics of "Impedance"

On a smooth velodrome, a hard tyre is faster because it reduces deformation. But on rough ground, a hard tyre (e.g., 50 psi+) cannot absorb impacts. When you hit a rock with a hard tyre, the entire bike—and you—are deflected upwards and backwards. That deflection kills your forward momentum. We call this "Impedance Loss."

The Suspension Effect

By dropping your pressure, you allow the casing to deform around the rock rather than bouncing off it. The bike stays level, and your energy pushes you forward, not up.

The Tubeless Requirement

To run these pressures safely, you really need to be set up tubeless. If you try riding these pressures with standard inner tubes, you will pinch-flat within the first hour.

Find Your Sweet Spot

Don't guess. Use this "Cheat Sheet" as a starting point. Notice how much lower you can go as the tyre gets wider.

Rider Weight	40mm Tyre	45mm Tyre	50mm Tyre
< 60kg	24 - 26 psi	21 - 24 psi	19 - 22 psi
60 - 70kg	27 - 30 psi	24 - 27 psi	22 - 25 psi
70 - 80kg	30 - 34 psi	27 - 31 psi	25 - 28 psi
80 - 90kg	34 - 38 psi	31 - 35 psi	28 - 32 psi
> 90kg	38 - 42 psi	35 - 39 psi	32 - 36 psi

Note: If the surface is rocky, add 2-3 psi to these numbers to protect your rims.

The Test

Start with these numbers. If it feels harsh, drop 1 psi. If you feel the tyre "squirm" or fold in a corner, add 2 psi immediately. If you want the exact science, I recommend the Silca Tyre Pressure Calculator.

Conclusion: Embrace the Gravel Challenge

Is there anything that can stop the chatter of riding over gravel completely? I found snow works... well until hypothermia strikes, then teeth chatter is the least of your concerns!

Gravel riding is a unique challenge. It tests your skills, your body, and your mental fortitude. But with the right knowledge and adjustments, you can conquer it. So, gear up, embrace the adventure, and enjoy every bumpy moment on the trail!