from planet-x/on-one...
"Never ridden a 29er? Imagine skipping cereal and eating miles for breakfast, using less energy and less pedal strokes to go the same distance as before. It's like waking up with legs a foot longer than they were last night and then going for a run. Imagine cruising past your bikey mates through a technical rock garden and then stepping on the gas and outpacing them by hundreds of meters. And when you stop pedalling you keep rolling ...and rolling. Save energy, save time, get a 29."
now then, where to begin?!!
'using less energy and less pedal strokes to go the same distance as before.'
Er, is there some magic contraption that injects power into a 29er wheel? No. Could travel further with less pedal strokes by simply increasing the gear on my 26er bike? Yes. Besides, 29ers run lower gears precisely so that the effective gearing is the same as a 26er.
'Imagine cruising past your bikey mates through a technical rock garden and then stepping on the gas and outpacing them by hundreds of meters.'
I don't expect that someone would be able to cruise over a rock garden on the limited number of full-sus 29er bikes any better than the vast majority of 26er full-sus bikes. Also, it takes more energy to accelerate a bigger wheel, so, on the contrary, a 26er would outpace a 29er in terms of acceleration.
'Save energy, save time, get a 29.'
Where is the proof for this? I think it simply makes a convenient rhyme.
In short, an almost entirely factually incorrect, load of nonsense.

