The nominal diameter of the bicycle wheels. Usually, this paragraph actually indicates the size of the bicycle tyres supplied in the kit, more precisely, the outer diameter of the tyres.
Wheel diameter is traditionally indicated in inches. For bicycles of different purposes and age groups (see paragraphs above), there are certain size standards. So, adult mountain models are equipped mainly with
26 " wheels, "road" and urban ones — with a slightly larger diameter (mostly
28 "), and BMX for the most part — much smaller; children's and teens' bikes have smaller wheels than similar adults' bikes.
Other things being equal, larger tyres hold speed better and work out small bumps on the road; and relatively small wheels are more “sticky”, they provide more torque and better traction. This is the reason for the above-described difference in wheel sizes between bicycles for different purposes. Such nuances will be useful if you choose a car from several models with similar characteristics, but different wheel diameters. Here it is worth considering the features of the planned application. For example, for urban and "road" driving — on a hard surface without any special irregularities and elevation changes — it is better to choose larger wheels, and for dirt roads with ups and downs — smaller ones.
Also note that tyres are replaceable, and many bikes allow the installation of tyres of
...a “non-native” size — for example, 29 "on a model with 28-inch wheels. It is also worth considering that wheels (tyres) of the same size may differ in inner (landing) diameter These nuances are described in detail in special sources.
