Rolling over obstacles
Whatever track you may be riding, you encounter rocks, roots and a variety of bumps trying to slow you down. Unless you are among those riders who can simply jump over these obstacles, you can see below which advantages a 29-inch wheel has to offer in this situation.
There are two forces acting on the wheel (FG – vertical force and FA- horizontal force, acting in the direction you move). The height between the wheel axle and the spot where the wheel touches the object on the track (D1) together with the length between the wheel axle and the spot where the wheel touches the object (D2), create a lever helping the wheel to overcome the obstacle. The higher the leverage, more easily you will pass over the object in your way (in our case, the height of the wheel, from its axle to the spot where the wheel touches the object is higher for a 29 inch wheel then for a 26 inch one).
Passing through holes / ditches
Impossible to avoid on almost any route, ditches can seriously slow you down. As you can see in the second image in our illustration, the 29-inch wheel rolls easily over such obstacles such as it has a greater diameter. A 26-inch wheel will only go deeper into the ditch slowing your pace. For this reason also, 29-inch wheels are considered to be more comfortable.
This is highly clear to everyone: a larger radius wheel with roll faster than one with a smaller radius. And this is exactly what happens in our case. Moreover, the contact patch of the 29-inch wheel is slightly longer and narrower than one of a 26-inch wheel. The comparison can be easily made using a tire from the same brand, with the same width and with the same pressure.
We may conclude the grip is also better, as more knobs touch the ground. Your opinion regarding the 29-inch wheels is welcome, so we invite you to share your experiences below.