Is Your Tire Choice Slowing You Down?
Choosing the right tire can significantly impact your race day performance.
Many athletes underestimate how much the right tire can improve their bike split time.
A common concern among triathletes is the risk of getting a puncture on race day.
This fear often leads athletes to opt for the Continental Gatorskin, known for its puncture protection.
But does this tire choice come with a time penalty? Let's find out.
The team at Bicycle Rolling Resistance has compared various tires, calculating rolling resistance and puncture scores for each.
Rolling resistance measures the force a tire exerts on a surface, quantified in wattage.
They also provide puncture scores; higher scores indicate better puncture resistance.
The table below showcases rolling resistance data for popular tire brands, including the tire model, tube type, required wattage at specific pressures, and watt savings compared to Gatorskins.
[Source: https://www.bicyclerollingresistance.com/road-bike-reviews] (Note: TLR/TR/TLE denotes tubeless tires; others use butyl tubes.)
The selected brands are common choices among triathletes for both training and races.
Lower rolling resistance means a faster tire, while higher puncture scores signify better puncture protection, albeit at the cost of speed.
The fastest tire in our selection is the Vittoria Corsa Speed G+ 2.0 TLR (tubeless) 25, boasting an 8.3 rolling resistance and a 33/22 puncture score.
On the other hand, the Continental Gatorskin is the slowest, with a rolling resistance of 22w and a puncture score of 89/19.
The Gatorskin's high puncture resistance is a key attraction for many cyclists.
Compared to the Gatorskin, you'd need 13.7 fewer watts to roll the Vittoria tire, potentially saving you up to 26 watts.
But what does all this data mean in practice?
Let's consider an example:
Imagine an athlete preparing for Ironman Busselton with the following specs:
Total weight, including bike, gear, and water bottles: 82 kg
Tire choice: Gatorskins 25mm
Tire pressure: 80 psi
Deep section wheels (up to 60mm deep)
Wearing an aero helmet
Goal time: 5 hrs 32 mins
FTP: 260w
Using Best Bike Split, we can model:
Aerodynamic drag or Cda
The impact of rolling resistance based on tire choice
The wattage needed to achieve the target time
When we apply these values to the Ironman Busselton course, the estimated wattage to meet the goal time is 200w for the 180K, which equates to 77% of their FTP.
What happens if we change only the tires while keeping everything else the same?
The table below reveals the wattage required for various popular race tires to meet the 5 hrs 32 mins target:
[Table showing wattage requirements for different tire selections]
As you can see, the three fastest tubeless tires require significantly less wattage, 30 to 35w less, to meet the race goal.
The two fastest clincher tires with butyl tubes, the GP 5000 and Michelin Power Time Trial, save about 25 to 29w.
But you might wonder, what if you maintain the same percentage of FTP for all tire choices?
The chart below estimates times while holding 77% of FTP or 200w:
[Chart showing estimated times]
For the three fastest tubeless tires, it's estimated to be 20 to 22 mins quicker than using Gatorskins, resulting in a bike split of 5 hrs 9 to 12 mins.
The two fastest clincher tires are estimated to be 16 to 19 mins quicker, with an estimated time of 5 hrs 13 to 15 mins.
This demonstrates the substantial impact of a simple tire change.
However, remember that these are estimates. Individual results may vary, but the overall trend should apply to you as well, resulting in improved times.
Factors to consider before making a decision include road surface, puncture resistance, technical ability for tubeless setup, and tire cost.
The table below displays the puncture resistance scores for the tires:
[Source: https://www.bicyclerollingresistance.com/road-bike-reviews] (Note: TLR/TR/TLE denotes tubeless tires; others use butyl tubes.)
[Table showing puncture resistance scores]
The Gatorskin has the highest puncture score. The three fastest tubeless tires have the lowest scores.
The GP 5000 offers a balance between protection and performance.
Moreover, there are alternative tube options, like Latex and TPU tubes, which can enhance the performance of clincher tires.
The tables below show the impact of using Latex or TPU tubes on rolling resistance for the GP 5000 and Michelin Power Time Trial:
[Source: https://www.bicyclerollingresistance.com/road-bike-reviews] (Note: TLR/TR/TLE denotes tubeless tires; others use butyl tubes.)
[Source: https://www.bicyclerollingresistance.com/road-bike-reviews] (Note: TLR/TR/TLE denotes tubeless tires; others use butyl tubes.)
[Tables showing the impact of tube types on rolling resistance]
As shown, Latex or TPU tubes make these tires perform closely to the fastest tubeless options, an excellent alternative for those not choosing tubeless.
To conclude, tire choice is a crucial factor that can save you valuable minutes on race day.