BikeRadar.com has a very interesting story about the facts and myths of bicycle tyres (or tires if you prefer the incorrect spelling :))Â The article explodes a few myths about tyres based on the work by the independent third-party tyre testers, Wheel Energy.
The full post at BikeRadar.com should be read for all the details but here is taste of what the people at Wheel Energy have found:
- Puncture resistance belts work but they can suck up energy depending on the material used;
- Wider tyres roll faster than narrower ones;
- Choice of tube, inner tube that is does matter;
- Bigger (diameter) wheels roll better than smaller wheels;
- Tread pattern, well some tread patterns matter on the road, not just on the single track;
- Higher thread counts do not always mean a better tyre – there are trade-offs.
As a standalone statement, “Wider tyres roll faster than narrower ones” is not true, it needs qualification. In the article you linked to 25mm tyres roll faster than 23mm tyres. However, there are limits. I have 32mm tyres that do not roll faster than 23mm tyres, in fact, they are about 10km/h slower at terminal rolling velocity down known hills. For more info refer: http://www.terrymorse.com/bike/rolres.html
In that study, at 9 kg/cm2 the best performing and worst performing tyres were 28C. Perhaps brand makes a bigger difference than width?
and tread pattern maybe?
Tread pattern makes a difference and pressure too. So, the variables are brand, width, tread and pressure. From the research I have done, it would appear if the other variables are correct then a 28c will roll best.