. Heb onderstaand onderzoek gevonden op internet. Efficiency Study:
The Effects of Mountain Bike Wheel Size on Performance in Uphill and Cross-Country Cycling
Authors: J.T. Herr and Holden S-H. MacRae
Department of Sports Medicine, Pepperdine University, Malibu, CA
Purpose: The purpose of this study was to assess the effect of wheel circumference on mountain bike performance during uphill and cross-country cycling.
Conclusion: Larger circumference wheels improve mountain bike performance during climbing and cross-country riding, with no detrimental effect on cardiovascular (heart rate) or muscle function (power output).
Summary: Our major performance outcome was time to complete each trial, since race performance is determined by who completes a given distance in the shortest possible time. The average times of the 6 cyclists tested were 4% faster (17 sec) on the uphill course, and 3% (26 sec) on the XC course when riding the 29” equipped bicycle.
If one extrapolates the duration of these trials to typical ride/race times of 1.5 or 2 hours, then it is likely that significant performance differences can accrue by riding a 29” equipped bicycle.
The practical significance of the faster course completion times of the 29” vs. 26” bicycle is illustrated by the effect size statistic for time completing the course. The effect size statistic is a calculation of the magnitude of the effect, in this case, that of riding the big wheel bicycle which was faster on both the uphill and XC trial. The number on the uphill course of 0.75, and on the XC course of 0.96, indicate a large effect from riding the 29” equipped bicycle. Most statisticians will say that a number greater than 0.5 is large. Thus, the effect here of riding the big wheel is likely very large, even though the trials were of short duration.
We attribute the faster course completion times on the 29” vs. 26” bicycle to the larger wheel traveling a greater distance per pedal revolution (average power outputs were not different between bicycles), and likely to a cumulative effect of the larger wheels rolling faster and more easily over obstacles during the uphill and cross-country trials.
The improvement in performance seen during climbing and cross-country riding with the 29” equipped bicycle, occurred without any detrimental effect on cardiovascular (heart rate response) or muscle function (sustained power output) even though the 29” bicycle was heavier that the 26” bicycle.
Presented at the South West Chapter of the American College of Sports Medicine Conference, Las Vegas, NV, November 2003
Maar Peter V maakt ansich wel een heel valide statement... 
Tis het wachten wel waard trouwens ! 
