The goal of this test was to evaluate the rolling resistance performance of tyres used whilst racing on velodromes, particularly indoor wooden velodromes.
WHICH IS FASTER - TUBULAR, TUBELESS OR CLINCHER?
Tubular tyres are fixed to wheel rims optimally using tubular cement/glue. Adhesive tubular tape can be used, but this results in slightly higher (worse) rolling resistance than using glue. The wheels used for tubular tyres are specific and have a tyre well in which the glue is spread, unlike tubeless/clincher wheels which have bead seats/hooks for the tyres to lock into when inflated.
"Faster" will also need to take into account the wheel the tyres are used with, and how aerodynamic the wheel is. Especially at the high track speeds of track racing, small differences in Crr can be overcome by a more aerodynamic wheel.
TUBULAR TRACK RACING TYRES
Vittoria Pista Speed 23mm
Vittoria Pista Oro 23mm
Continental Sonderklasse 23mm
Continental Olympic 19mm
Continental Tempo 22mm
Veloflex Record 23mm
Veloflex Record 25mm
Dugast Pista Latex Silk 22mm
CLINCHER TRACK RACING TYRES
Vittoria Pista Oro 23mm
Veloflex Record 23mm
Continental GP5000 TT 25mm
Vittoria Corsa Speed 23mm
Vittoria Corsa Pro Speed 24mm
Vittoria Pista Control 23mm
In order to test rolling resistance, we swapped between the tyres as a rider rode a bike on rollers, measuring power output and speed, as well as atmospheric conditions and bike/rider weight, repeated over a number of days testing. This allows us to calculate what is known as the Coefficient of Rolling Resistance (or "Crr"), which can be used to model the power output required to travel on a normal road. A lower Crr is better - in that it requires less power to travel at the same speed.
All tubular tyres were fitted to a tubular aluminium rim using Continental rim cement in multiple cured layers, and inflated to 150psi.
Clincher/TLR tyres were all mounted using a Vittoria latex inner tube. In previous testing we have found no difference between tubeless sealant of ~30ml and a latex tube, and we do not recommend using tubeless sealant in a track scenario.
Some clincher tyres were inflated beyond manufacturer stated maximum pressure - this is for information only and we do not recommend inflating tyres beyond their stated maximum pressure.
In this test, we found that the fastest tubular tyre (at 150psi), a Dugast Pista Latex Silk 22mm was nearly identical to the fastest clincher tyre, a Vittoria Pista Oro 23mm when inflated to 130psi. This is however beyond the max stated pressure for the Pista Oro, and the next fastest clincher tyre was a Veloflex Record 23mm at 130psi, 0.6w slower than the Dugast for a pair of wheels at 55kph.
A rolling resistance change of 0.6w is worth around 25m over an hour record at 55kph.
The tubular tyres tested, when inflated to 150psi were much narrower than their clincher/TLR equivalents. For example the Dugast Pista Latex Silk 22mm was nearly 4mm narrower than the Vittoria Pista Oro 23mm clincher at 130psi.
Because of the small differences between tyres at these pressures, it is critical to understand the aerodynamic performance of a chosen wheel/tyre combination, as the aerodynamic contribution to resistive forces can outweight small changes in Crr.
In this test we have found that modern clincher tyres, when inflated to high pressures, return very similar Crr values to tubulars that are also inflated to high pressures.
The correct pressure for a given scenario will change - on exceptionally smooth velodromes higher pressures are able to be used, in excess of the 150psi tubular pressure used in this test, but this will vary depending on track surface.
Because of the importance of aerodynamics at high track speeds and the closeness of Crr between tubulars and clinchers, the aero performance of wheels should be foremost when deciding on equipment choice, with tyre type secondary.