Is big best?
The study, conducted by a team of Swiss scientists, used the Swiss National Cross Country team to test the differences between the wheel sizes.
The athletes were sent out on a course that was split into two: the first half “consisted of more straights, downhills, wide turns and a rougher surface (roots, stones)” thought to favour a 29er, while the second half had “more uphills and more tight, winding trails” to aid the 26 inch wheel.
Each athlete (seven male, three female) completed six laps of the course and their time was analysed by the scientists. The athletes were also asked to rate their personal experience on the bikes.
Watch highlights of the Val di Sole XCO WOrld Cup won by Swiss National rider, Nino Schurter
The scientists found that the 29 inch bikes were 2.4 per cent quicker overall than the 26 inch bikes and they were also 0.3 km/h quicker on the sections thought to favour the 26 inch bikes. All the athletes did their fastest run on the 29 inch bike.
The athletes also rated the 29 inch bikes as better over obstacles and for having superior traction.
The study conluded: “The benefits of the 29“ bike are most pronounced on courses where traction between tyre and surface, passing of small obstacles (tree roots, stones) and positive overall riding characteristics of the bike are important. For these reasons, we support the use of the 29“ bike for all elite MTB-XCO athletes.”
It is worth noting that 2.4 per cent is quite a small margin so unless you are a racer or an elite athlete you will probably be just as happy on any wheel size. It’s good to know though that, when pushed to their limits, bigger wheels are objectively better.
This is the first study that has used Elite level athletes to test how wheel sizes affect performance.
Thomas Steiner, Beat Müller, Thomas Maier & Jon Peter Wehrlin (2015): Performance differences when using 26- and 29-inch-wheel bikes in Swiss National Team cross-country mountain bikers, Journal of Sports Sciences, DOI: 10.1080/02640414.2015.1119294
To read the study click here.