What is the best wheel diameter for a mountain bike 26 "; 27.5"; 29 "?

Until recently, cyclists did not think about which size of bicycle wheel to prefer. The vast majority of cycling enthusiasts purchased a mountain, road or pleasure bike with 26-inch wheels. The remaining cyclists, disregarding bicycles for children, chose either road bikes with 28-inch wheels, BMX or City bikes.

 It would seem that there is already everything in the bicycle industry, everything was invented, but progress has once again broken the established world of cyclists. What was the only possible choice was suddenly one of the possible options. There was a time when the "newly made" aluminium frames seemed to be completely absurd, but in the end they squeezed the steel frames, and later carbon-fiber frames appeared, which "come" in the same way with aluminium ones. About 5 years ago, mountain bicycles with 29-inch wheels began to gain popularity, but at the moment 29-inch wheels are more competitive with 27.5-inch wheels.

Choosing the right wheel diameter.

In the world there are several thousand bicycles of various models and types with wheels 26 inches. Each of them is designed either for a particular riding style or is universal - combining several classes. At least several dozen of these models can be considered truly worthwhile. Several hundred of these bikes are excellent in handling, have excellent driving characteristics and provide good ride comfort. The remaining 26-inch is distributed on a scale from good to very bad. Professional athletes participating in international championships use bicycles made individually for each. Cyclists who compete in less significant cycling competitions, acquire for themselves top models of mass production, they also include amateurs with great financial opportunities. The overwhelming majority of cyclists ride on what they have had enough money for. And they all drove, participated, won, enjoyed ... And suddenly, a new business idea invaded their sports world.

Not being able to improve the bike and its characteristics by intensive development, they invented another new-fangled nonsense, which in our time is quite easy to promote to the masses with the help of advertising. For example, we can say that 26-inch wheels are too small and this is the last century, and make 29-inch. Come up with all sorts of immeasurable positive qualities of the "improved" subject and make a lot of money with it.

The main advantages of 29-inch wheels in relation to the 26-inch, which they say marketers:

Better roll.

It is safe to say that a huge number of cyclists have no idea what this means. They also do not know why the bike does not fall when it goes and falls when it stands still. But for lovers of two-wheeled vehicles, this is completely useless; the main thing is that the “great” should be comfortable and drive well. Marketers, in turn, say - due to the larger diameter, the wheels roll much better and make the bike more stable due to the increased gyroscopic effect. Maybe the term "rolls" means that the bike travels longer due to inertia, which in this case is true, since the stock of inertia depends directly on the diameter and mass of the wheel. But, the more massive the wheel, the more difficult it is to unwind it at the start, or to stop it at braking. With the same success, you can use the 26-inch wheel, but heavier. So this quality should rather be considered as negative rather than positive.

The angle of irregularities and obstacles, as well as comfort while driving is much better.

 The usefulness of such dignity 29-inch wheels is difficult to argue, since the wheels of smaller diameter have a greater angle of "attack" when overcoming obstacles in comparison with larger wheels. Large wheels are easier to cope with various protrusions and small pits. Some sources even write that the opposing force from obstacles is reduced by about 10%. Incredibly, by as much as 10%. For example, if you imagine that one cyclist rides on standard 26-inch wheels, and the second on 29-inch wheels, and both accidentally bump on a 5-cm-high stone, then this stone will not look like a second 5-cm stone, but less than 5 mm. just fantastic. You can also imagine a cyclist who decided to enter a 15-centimeter curb without lifting the wheel, and again an incredible miracle, the bike driver experiences such a push from the curb as if it is less than 2.5 cm. Of course, if you drive a hardtail with 29-inch wheels for a long time, even across rough terrain, fatigue will decrease by about 10%.

The larger the wheel diameter, the greater the contact patch of the tire with the road surface - this is another trick of marketers.

They also say that because of the greater adhesion of the tire to the road, the effectiveness of braking and starting without slipping increases. It turns out, if you do not want to slip at the start (and how to start it so that there are slip), you need to purchase 29-inch wheels. It is easier to put the wide tires or not to over pump the wheels. In addition, with an increase in the clutch stain with the track, the friction force also increases, which in turn slows down the movement.

The ability to develop greater speed at lower physical cost.

And again, you can’t argue, everything is logical. If the axes of wheels of different sizes have the same speed, then a wheel with a larger diameter goes a longer way, therefore, has a higher speed. But due to the use of the gearshift system, this advantage of the 29-inch wheels is diminishing. The wheel axle can rotate at different speeds, across a wide range of gears. To ride a bike at a higher speed, you absolutely do not need to change the diameter of the wheel, it’s enough to switch the speed. On old bicycles, which have only one speed, large diameter wheels could provide this effect.


It's not about what kind of wheels the bike is equipped with, but about the correct gear changes, the width of tires, the level of atmospheric pressure in the tires, and what level the bike itself and the physical preparation of the biker. At major events devoted to cycling, during bicycle parades all this is perfectly visible. Some riders, on domestic bikes like "Private label”, ride along with the majority, and there are cyclists who ride on 26-inch wheels and overtake everyone. And the point here is that they are just actively involved in cycling. There are also such amateurs who win at the expense of a good bike and its excellent setting. Due to the fact that the production of bicycles with 26-inch wheels decreases every year, and the production of wheels with a diameter of 27.5 inches increases, apparently the latter are trying to make a new standard for mountain bikes, and you cannot get away from it.

 In general, when choosing the diameter of the wheels of a bicycle, you should be guided by the conditions under which you plan to use it. For simple trips around the city or short bike trips, a bike with a smaller diameter will do; for cycling trips with long trips and a small number of stops, it is better to buy a 29 "bike. Professional athletes themselves know that they are better off and they won’t know anything new from this article.

 I wish you a good choice

  • Feb 13, 2019
  • Category: News
  • Comments: 0
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