With all the attention cycling performance gets — FTP, aerodynamics, weight savings — one crucial force still flies under the radar for many athletes: rolling resistance. It's always there, quietly taxing your watts on every ride and race. Since we first published this article a decade ago, tire technology has advanced dramatically, and a whole new category of inner tube has emerged. It's time for a comprehensive update.
The Short Answer: The Coefficient of Rolling Resistance (Crr) is a dimensionless number typically in the range of 0.002–0.007 for road bike tires. The lower the Crr, the faster the tire rolls. It's the energy lost as your tire deforms and recovers with each wheel rotation.
What Is Rolling Resistance, and Why Does It Matter?
Rolling resistance is the energy lost as your tire deforms and recovers with each wheel rotation. Every time the contact patch flattens against the road and then springs back, heat is generated — and that heat represents power you produced that didn't move you forward. On hard surfaces like pavement, the primary source of this loss is hysteresis: the internal friction within the tire casing and rubber compound as it deforms under load.
The physics are captured in the Coefficient of Rolling Resistance (Crr), a dimensionless number typically in the range of 0.002–0.007 for road bike tires. The lower the Crr, the faster the tire rolls. At race speeds, rolling resistance typically accounts for 10–20% of total power demand — comparable in scale to aerodynamic drag at lower speeds, and far more significant than most riders realize.
The force required to overcome rolling resistance is:
F_rr = Crr × W × g
Where W is total system weight (rider + bike) in kg and g is gravitational acceleration. Critically, the power required to overcome this force scales linearly with speed — so the faster you go, the more watts rolling resistance costs you in absolute terms.
How Crr Is Measured: The Bicyclerollingresistance.com Standard
When we originally built the rolling resistance model in Best Bike Split, we pulled data from every source we could find and ran it through a machine learning model. The key drivers we identified — tire width, tire type, and tube type — still hold true today. But our ability to get precise, standardized data has improved enormously.
Bicyclerollingresistance.com has become the gold standard for tire rolling resistance data, now having tested hundreds of road, gravel, and mountain bike tires on a controlled drum under standardized conditions (typically 29 km/h / 18 mph, 42.5 kg load). Their data is what Best Bike Split uses to calibrate its Crr model, and it's what you should use when selecting your tire value in BBS.
To find your tire's Crr:
- Visit bicyclerollingresistance.com
- Look up your tire in their comparison chart
- Find your Crr value at your expected inflation pressure
- Enter that value into your BBS bike settings
This gives our model the precision needed to translate tire choices into real predicted time differences on race day.
The Tire Landscape Has Changed
When we first wrote this article, the benchmark clincher was the Continental Grand Prix 4000s II, and tubular tires were still considered by many to be the gold standard for speed. A decade later, the picture looks completely different.
Tubeless Has Arrived — and It's Fast
Tubeless road tires have matured significantly. Running without an inner tube eliminates the friction between tube and tire casing, and the ability to run lower pressures without pinch flat risk can actually reduce rolling resistance on real-world road surfaces compared to higher-pressure setups with tubes.
The current benchmark all-round tubeless road tire is the Continental Grand Prix 5000 S TR, measuring around 9.7W at 29 km/h in 28mm width on bicyclerollingresistance.com's testing rig — a massive improvement over the original GP 4000s era. For pure speed, the Vittoria Corsa Pro Speed TLR currently leads all tested tires at just 6.7W, using a ultra-thin tread and cotton casing with no puncture protection strip, relying on sealant to handle small punctures.
Here's a snapshot of where the fastest road tires stand today:
| Tire | Type | Watts (29 km/h, 28mm) |
|---|---|---|
| Vittoria Corsa Pro Speed TLR | Tubeless | 6.7W |
| Continental Grand Prix 5000 TT TR | Tubeless | 8.3W |
| Continental Grand Prix 5000 S TR | Tubeless | 9.7W |
| Michelin Power Time Trial | Clincher | 10.6W |
| Continental Grand Prix 5000 | Clincher | ~12W |
| Continental Gatorskin / Gator Hardshell | Clincher | 18–22W+ |
Compare that last row to what we highlighted in our original article — the Gatorskin's Crr of ~0.006 is largely unchanged, but the gap to the fastest tires has grown as the top end has gotten significantly faster.
Wider Tires Are Generally Faster
One of the clearest conclusions from years of data is that — up to a point — wider tires have lower rolling resistance, not higher as was once assumed. A 28mm tire at the right pressure rolls faster than a 23mm tire inflated higher, because the contact patch is shorter and rounder, reducing tire deformation. Most triathletes and road racers have moved to 25–28mm as the performance sweet spot, and this is now reflected in our BBS Crr baseline values by tire width.
The Inner Tube Revolution: TPU Changes Everything
The biggest development since our original article is the emergence of TPU (Thermoplastic Polyurethane) inner tubes as a legitimate third option alongside butyl and latex.
Here's how the three materials compare:
Butyl
The decades-long standard. Affordable, easy to patch, widely available, and holds air well. But it's the heaviest option (typically 80–120g) and has the highest rolling resistance. For training, commuting, or budget setups, butyl remains perfectly adequate — but for racing, it leaves performance on the table.
Latex
Latex has long been the performance rider's secret weapon. Its natural elasticity lets it deform and recover with less energy loss, reducing rolling resistance by roughly 3–7 watts per pair compared to standard butyl at racing speeds. Latex tubes also weigh around 60–80g, a meaningful saving over butyl. The trade-offs are real though: latex loses air faster (often requiring pre-ride inflation), is harder to patch, and is less puncture-resistant than butyl.
TPU (Thermoplastic Polyurethane)
TPU tubes are the newcomer that's reshaping the conversation. Made from a lightweight plastic, the lightest TPU tubes weigh as little as 20–30 grams — roughly a third to a quarter of a standard butyl tube. Rolling resistance sits very close to latex, with independent testing by bicyclerollingresistance.com showing top TPU tubes saving 3–5 watts per pair over butyl. Some ultra-light TPU options come within a fraction of a watt of latex performance.
Where TPU wins over latex: it retains air far better (check it once a week rather than before every ride), is more durable and puncture resistant, is recyclable, and packs into a tiny pouch ideal for carrying as a spare.
The practical bottom line for racers who want to run clincher setups: TPU tubes with a fast tire (like the Michelin Power Time Trial) can match or approach tubeless performance with none of the sealant maintenance.
| Tube Type | Typical Weight | Rolling Resistance | Air Retention | Puncture Resistance |
|---|---|---|---|---|
| Standard Butyl | 80–120g | Baseline | Excellent | Good |
| Latex | 60–80g | ~5–7W savings vs butyl | Poor (check before each ride) | Fair |
| TPU | 20–45g | ~3–5W savings vs butyl | Very Good | Very Good |
What's the Real-World Impact?
The core relationship hasn't changed: Crr and rider weight combine to determine rolling resistance force, and power cost scales linearly with speed. But let's put today's tire options into context with a real-world example.
Consider an age group triathlete averaging 200 watts over an Ironman bike course. Using updated Crr values:
| Tire / Setup | Estimated Crr | Estimated Time (Kona course, 200W) |
|---|---|---|
| Continental Gatorskin (training tire) | 0.0060 | 5:16:00 |
| Continental GP 5000 (clincher, butyl) | 0.0040 | 5:08:00 |
| Continental GP 5000 S TR (tubeless) | 0.0031 | 5:03:30 |
| Vittoria Corsa Pro Speed TLR (tubeless) | 0.0022 | 4:59:00 |
That's nearly 17 minutes separating a high-quality training tire from the fastest available race tire — and over 8 minutes between a solid clincher with standard tubes and a top-tier tubeless setup. For an age grouper, that's enormous.
For an elite athlete, the margins are smaller in time but potentially more decisive. With race outcomes increasingly decided by minutes or seconds at the top of the field, even a 30-second improvement from tire selection is meaningful — and Crr changes in that range are very achievable.
How to Use This in Best Bike Split
Here's how to apply all of this in BBS:
- Look up your tire on bicyclerollingresistance.com — search for your specific model, width, and intended inflation pressure.
- Note the Crr value from the Rolling Resistance Test Results table at your expected race pressure.
- Enter it in your bike settings under the Crr field.
- Use the Time Analysis Tool to model what-if scenarios — swap a tire, change a tube type, and see exactly how many seconds that changes your predicted finish time.
If your specific tire isn't listed, the BBS default values by tire category (road clincher, tubeless, tubular, etc.) and width are reasonable starting points built from our updated database.
Adjusting the Crr slider to 0.00312 (Continental GP 5000 S TR) versus a typical training tire at 0.006 shows a 5+ minute swing on the Kona Ironman course — from a tire choice alone.
Practical Recommendations by Rider Type
Ironman or Long Course Triathlete
Tubeless is the sweet spot — low rolling resistance with good puncture protection from sealant. The GP 5000 S TR or similar fast tubeless tire in 25–28mm, properly inflated for course conditions, is an excellent choice. Avoid training tires on race day; the time difference is measurable and meaningful.
Road Racer or Gran Fondo Rider
If your rims support tubeless, it's worth the setup. If not, a fast clincher like the Michelin Power Time Trial with latex or TPU tubes can get you very close to tubeless performance. TPU is increasingly the recommendation here for the combination of speed, weight, and convenience.
Time Trialists
Go for the fastest tire you can tolerate the puncture risk of — the Vittoria Corsa Pro Speed TLR or Continental GP 5000 TT TR if tubeless, or the Michelin Power Time Trial with latex tubes if not. Model the exact impact in BBS before race day.
Training or All-Weather
The Continental GP 5000 All Season or Pirelli Cinturato Velo TLR offer a strong balance of speed and durability. The Gatorskin remains a worthy choice for rough roads or high puncture-risk training environments — just know the Crr cost and don't make the mistake of racing on them.
The Bottom Line
Rolling resistance isn't glamorous, but it's one of the most accessible performance gains available to any cyclist. The best news: unlike aerodynamics or fitness, a tire swap is inexpensive and immediate. Switching from a training tire to a quality race tire — and dialing in your pressure — can deliver 5–15 minutes of free speed over an Ironman distance.
Use Best Bike Split to quantify exactly what your tire choice means for your specific race, body weight, course, and target power. Enter your Crr, run the scenarios, and make an informed decision. The data is out there, and now you know how to use it.
