TREADIVO.

Rolling out across Australia

TREADIVO
Choose your location.
Back to blog

Rolling Resistance Ratings for Cyclists: Warm Tyres, Real Road Watts

Sketches of a tyre and testing equipment

A rolling resistance rating tells you how much energy a tyre wastes to deformation as it rolls, expressed as a coefficient called Crr. Lower is better for efficiency, full stop, but published numbers come from specific lab conditions and shift once you add road surface, temperature and pressure. For racing or long steady efforts, even small Crr differences translate into real watts and seconds.

TL;DR:

  • Lab rankings can invert on track because drum curvature, changing loads, roll angle, and speed alter tire behavior; compare results only under similar conditions.
  • For rough roads or gravel, lower pressure can reduce vibration losses; start within the recommended range, then reduce pressure by 5 to 10 psi.
  • Check test speed, load, pressure, whether tires were warmed up, and repeated runs before comparing Crr figures, since bicycle tires have no universal rating label.
  • Prioritize low Crr for smooth, long races, but choose grip, puncture protection, and water clearance over tiny efficiency gains on wet or mixed terrain.
  • At 35 km/h, reducing Crr from 0.006 to 0.004 saves roughly 5 to 6 watts per tire for an 85 kilogram rider and bike.
Treadivo
Find tyres suited to your car
Treadivo lets you search by car model or tyre size, compare transparent pricing, and choose a local fitter for your vehicle.

Table of Contents

What rolling resistance (Crr) and rolling-resistance rating actually are

The coefficient of rolling resistance, or Crr, is a dimensionless number that describes how much force it takes to keep a tyre rolling relative to the load pressing it down. A Crr of 0.005 means the rolling resistance force equals half a percent of the weight on that tyre. Road tyres typically sit somewhere between 0.003 and 0.012 depending on construction and test conditions, with the gap between the fastest and slowest models often larger than most riders expect.

The physical cause is hysteresis: every time the tyre casing and tread flex under load and spring back, the rubber does not return all the energy it absorbed. Some of it converts to heat instead of motion, and that lost energy is what a rolling-resistance rating actually measures. Softer, more supple casings generally lose less energy this way, which is part of why high thread-count casings tend to score better.

A single rating is only one slice of tyre performance. It says nothing about puncture resistance, cornering grip or wear life, and it was measured under one speed, load, pressure and temperature combination that may not match your riding. Treat a Crr number as a comparison point, not a complete verdict on a tyre.

How rolling resistance is measured: lab methods and field methods

Most published ratings come from drum testing. A tyre is pressed against a rotating steel drum at a set load and pressure while a sensor measures the force needed to keep the drum spinning. It is repeatable and controlled, which is why most manufacturer and media comparisons rely on it.

Bicycle tyre rolling against a steel test drum

Coastdown testing takes the opposite approach: a wheel or bike is set rolling and testers measure how quickly it decelerates, backing out aerodynamic drag to isolate rolling losses. It is closer to real riding but harder to control precisely because wind, road camber and rider position all creep in.

Reputable test reports disclose the variables that shape the result:

  • Test speed, since Crr changes with velocity.
  • Applied load, matched to realistic rider and bike weight.
  • Tyre pressure at the time of testing.
  • Ambient and tyre temperature.
  • Drum diameter and curvature, which affect how closely results mirror flat-road riding.

Lab and field numbers can diverge because a drum’s curvature flattens the tyre differently than a real road does, and because track and on-road testing introduces load shifts, roll angle and speed changes that a stationary drum cannot replicate. Research from Politecnico di Milano combining laboratory and on-track testing found that relative rankings between tyre sizes can actually invert once you move from drum to track, meaning the “fastest” tyre in a lab chart is not guaranteed to be fastest under race-day loads and speeds.

Typical rolling-resistance numbers and how to read a rating

Road racing tyres typically land between roughly 0.003 and 0.006 Crr at racing pressures, gravel tyres run higher at around 0.006 to 0.010 due to larger tread and more supple but heavier casings, and knobby mountain bike tyres can exceed 0.015 on pavement because tread blocks squirm and deform.

Crr ranges for three bicycle tyre types

To turn a Crr difference into something tangible, rolling resistance power loss is roughly Crr multiplied by weight multiplied by speed. At 35 km/h with a combined rider and bike weight of 85 kilograms, dropping Crr from 0.006 to 0.004 saves in the order of 5 to 6 watts per tyre, which over an hour-long effort can be the difference between holding a wheel and losing it. At lower speeds or shorter rides, the same delta matters less in absolute time but still adds up over distance.

For a commuter or weekend rider, a few watts rarely changes the ride. For someone racing time trials, criteriums or long steady-state events, those watts are often the cheapest performance gain available, cheaper than most equipment or training changes.

What changes a tyre’s rolling-resistance rating in the real world

Published Crr numbers are a starting point, not a fixed property of the tyre. Several real-world factors move the number up or down from what the lab reported.

Tyre pressure sits at the centre of a trade-off: higher pressure reduces casing deformation and lowers Crr on smooth surfaces, but on rough roads it increases vibration losses as the tyre bounces instead of absorbing bumps, a phenomenon researchers call surface impedance. Past a certain point on rough tarmac or gravel, dropping pressure slightly can actually lower real-world rolling resistance even though lab Crr at that pressure looks worse on glass-smooth drums.

Temperature plays a larger role than most riders assume.

Pro Tip: Give a cold tyre five to ten minutes of riding before trusting it to feel as fast as it tested.

A tyre can take several minutes to reach steady-state temperature and Crr, according to simulation and measurement work on transient rolling resistance, and the same research notes that temperature or speed-related Crr shifts can be large enough to match the effect of notable pressure changes. Cold starts, early morning rides and short errands all mean riding at higher-than-rated resistance for longer than expected.

Other factors worth tracking:

  • Casing construction and thread count, which govern how efficiently the tyre flexes and recovers.
  • Tread pattern and depth, where smoother, shallower tread generally loses less energy on pavement.
  • Inner-tube material and mounting method, since latex tubes and glued tubular mounting tend to outperform butyl tubes and taped setups in tubular tyre testing.

How to use rolling-resistance ratings to choose and set up tyres

Let the lowest published Crr drive your choice when you race time trials, long road events or anything where marginal watts decide outcomes and the surface is smooth and predictable. Let other factors outrank Crr when you ride mixed or rough terrain, need puncture protection for commuting, or ride in wet conditions where grip and water clearance matter more than a half-watt saving.

Tune pressure to your situation with a few deliberate steps:

  1. Start from the tyre manufacturer’s recommended pressure range for your tyre width and rim.
  2. Adjust down from the top of that range as rider weight decreases or road surface roughens.
  3. Drop another 5 to 10 psi for gravel or chip-seal roads to reduce vibration losses, even though lab Crr would suggest otherwise.
  4. Re-check pressure before long rides, since tubes and tubeless systems lose pressure over days.

Before trusting any headline Crr figure, check the report for test speed, applied load, pressure, whether the tyre was allowed to warm up, and whether the result was repeated across multiple runs. A single untested run at an unstated pressure tells you very little.

Pro Tip: A published Crr without a stated test pressure and load is a number you cannot compare to anything else.

Reading test reports and ratings: practical caveats

Demand four details before trusting a comparison: test speed, tyre pressure, whether the tyre was warmed up, and whether results were repeated for consistency. A “fastest tyre” headline often hides trade-offs like thinner puncture protection or a narrower pressure range that only performs on smooth tarmac. Check whether the test surface and load resemble your own riding before assuming the ranking transfers.

Bicycle tyres have no single mandatory rating label the way passenger vehicle tyres do in some markets. Motor vehicle tyres sold under European regulations carry rolling-resistance class bands as part of a wider efficiency label, a system described in UNECE’s WLTP rolling resistance documentation, which groups tyres into classes to help buyers compare fuel efficiency at a glance. That framework exists for cars and light vehicles, not bicycles, and it is worth knowing so you do not assume a similar official bicycle standard exists where none does.

For bicycle tyres, Crr figures mostly come from independent test labs and media outlets using drum or coastdown methods they disclose themselves, rather than from a universal certification body. That means two tyres rated by different labs are not always directly comparable unless the test conditions line up. When comparing tyres for your own setup, prioritise results from testers who publish their full methodology, including drum diameter, pressure and load, over single headline numbers lifted out of context. The absence of a standard label is also why checking a test’s stated conditions matters more for bicycle tyres than it does when buying a car tyre with a government-mandated rating on the sidewall.

What rolling resistance numbers mean for your riding

Low-Crr tyres offer the biggest real gains to racers and riders doing long steady efforts on smooth roads, where a handful of watts compounds over an hour or more. For everyday riders mixing surfaces and prioritising comfort or puncture protection, the gap matters less than pressure, tread choice and tyre condition. Verify any headline number against your own pressure and road before chasing a rating on a spec sheet.

— Areesh

FAQ

Is higher or lower rolling resistance better?

Lower rolling resistance is better because it means less energy is lost to tyre deformation as you ride, so more of your effort goes into forward motion. A tyre with a lower Crr at the same pressure and load will generally feel faster and require less power to hold a given speed.

How do I calculate rolling resistance?

Rolling resistance force is calculated as Crr multiplied by the normal load on the tyre, and the power lost to it is roughly that force multiplied by your speed. Lab testers measure Crr directly using drum or coastdown methods that isolate rolling losses from aerodynamic drag.

What is the 105% rule in cycling?

If you have seen a term used elsewhere, it is worth checking the original source’s definition before applying it, since it is not a standard industry metric.

What is the lowest rolling resistance tire?

The lowest Crr figures reported in independent lab testing typically belong to supple, high-thread-count road racing tyres run at higher pressures on smooth drums, often in the 0.003 to 0.004 range. Rankings shift between labs and conditions, so the single “lowest” tyre depends on which test methodology and pressure you are comparing.

What affects rolling resistance the most in real-world riding?

Tyre pressure and temperature tend to cause the largest shifts from a tyre’s lab-rated Crr, since cold tyres and rough surfaces both increase real-world losses. Research into transient rolling resistance found temperature-related changes can match the effect of a 100 kPa pressure drop, which is why warm-up and surface matter as much as the headline number.

Sources

Ready for new tyres?

Search your tyre size and see live prices, with fitting or pickup anywhere in Australia.

Shop tyresBack to blog