Schwalbe’s new Ironman is the official tyre of the international competition series to be staged by the World Triathlon Corporation (WTC). With Schwalbe and the WTC, two companies that fulfil highest requirements in their own sectors are committed to pooling their strengths in the future.
Ironman stands for the long distance of the triathlon with 3.8 kilometres of swimming, approx. 180 kilometres of cycling, and a marathon. In the cycling segment, aerodynamics is of vital importance. Triathletes ride special time-trial bicycles with aerodynamically optimised wheels. “With a width of 22 millimetres, we have tuned the dimensions of the tyre perfectly to suit this purpose”, said Christian Lademann, Road/Triathlon Product Manager at Schwalbe. “This saves the athletes a great deal of energy. In the 180 kilometre cycling segment at a speed of around 40 km/h, riders need to produce an average of 300 watts. The new tyre dimensions reduce this by about 10 watts. This saves a whole three minutes in terms of time!”
In complex wind channel tests, Schwalbe determined the tyre width that produces the least aerodynamic drag for the entire wheel system. In this context, the 22 mm tyre width was by far the best, whereas both the conventional 23 mm tyre width, as well as the widths 20 and 25 mm, showed a significantly higher aerodynamic drag. The tests also showed that an additional component at the interface of the tyre to the modern aero wheel rim is unnecessary, as the air flow follows the contour of the wheel rim.
Due to the wider rim width of the aerodynamically optimised wheels, all tyres will, in practice, become slightly wider again. As the space for the tyres is usually limited in the case of time trial bicycles, with a width of 22 mm, the Schwalbe Ironman also offers an advantage in this respect.
The rubber compound
A triathlon – that is also Schwalbe’s new, internationally unique triple rubber compound. It has the lowest rolling resistance of all Schwalbe rubber compounds to date. The combination of three individual rubber compounds eliminates the conflicting objectives of rolling resistance, wet grip and a long service life. “Our new RaceStar Triple Compound is based on modern polymers which have only recently become available”, said Christian Lademann. Around 1,000 rubber compounds and more than 40 prototypes were tested by Schwalbe in the laboratory and in practice before it was decided which three compounds to use for the Schwalbe Ironman.
As far as the tread was concerned, Schwalbe chose an aerodynamically optimised, high-traction, grooved tread that covers the whole side wall and gives the tyre a very dynamic appearance.
THREE SYSTEMS:
Folding, tubular and tubeless tyres
As Schwalbe’s first folding tyre, the Ironman has been approved for a maximum pressure of 11 bar. “Such a high pressure is not recommendable on the majority of roads, but on time-trial segments with a very homogeneous road surface, the high air pressure reduces flexing and is, thus, an advantage in terms of rolling resistance”, explained Christian Lademann. “In addition, the tyre can be pumped up a bit more without hesitation if the bike has to be handed over for the competition the day before.”
In addition to the folding tyre version, the Schwalbe Ironman is also available as a classical hand-sewn, tubular tyre and in a modern tubeless version. Christian Lademann sees the change of system to tubeless tyres as positive: “Up to now, there have been virtually no tubeless tyres for racing bikes. However, in practice, this system offers excellent advantages. There is considerably less rolling resistance than with classical folding and tubular tyres, because there are no frictional losses between the tyre and the inner tube. At the same time, tubeless systems are extremely safe. A sudden loss of air is virtually impossible. There are no longer any inner tubes that can overheat and burst. A puncture protection fluid seals punctures immediately.”
The Schwalbe Ironman in the size 22-622 will be available as from May.
Price: around 45 Euros for the folding tyre, around 65 Euros for the tubeless version and 85 Euros for the hand-sewn tubular tyre.