Comparison Discovery Attack DD 26 2020 vs Discovery Flint AM DD 24 2020

The age group to which the bike belongs. This parameter in our catalogue is indicated only for teenage models; if the age group is not specified, it means that the car belongs to “adults” (children’s bikes are placed in a separate section of the catalogue).

Teenager bikes are designed for teens aged about 10-14 years old, for whom children's bikes are already small, but adults are still too big. Such bicycles are similar in design to adults and differ from them mainly in slightly reduced sizes — in particular, the diameter of the wheels (see below) in them usually does not exceed 24 "(there are exceptions, but extremely rarely).

The maximum load allowed for a bicycle is, in other words, the maximum weight that it can normally carry in normal use. Of course, when calculating the load, the weight of both the cyclist himself and the additional load that he carries with him is taken into account.

The permissible load must definitely not be exceeded: even if the bike does not break down immediately, off-design loads can weaken the structure, and an accident can occur at any time. Also note that it is desirable to have a certain weight margin — at least 15 – 20 kg: this can be useful in case of transporting heavy loads and will give an additional guarantee in emergency situations (for example, when a wheel gets into a pit). Considering that the average weight of an adult is about 70 – 80 kg, bicycles with a permissible load of up to 100 kg can be classified as "lightweights", from 100 to 120 kg — to the middle category, more than 120 kg — to "heavy trucks".

The presence or absence of a depreciation system on a bicycle, as well as the type of this system.

— Without depreciation (rigid). In such models, the wheels are fixed directly to the rigid elements of the frame; there are no depreciation devices. Due to this, the design of the bicycle is simple, the weight is small, the cyclist feels all the features of the road topography as much as possible, and the maximum efficiency of pedaling is also achieved, which is important, for example, for road models (see "Destination"). At the same time, structural rigidity is a "double-edged sword". On the one hand, "feeling for the road" is important for BMX and some mountain models (see "Purpose"); on the other hand, the lack of shock absorption significantly increases the load on both the structure and the rider himself, leads to increased wear, fatigue and some risk of injury on rough roads.

— Depreciation of the front fork (hard tail). The most popular type of cushioning in adult bikes (see "Age Group"), especially urban and mountain types (see "Purpose"). In accordance with the name, in such bicycles, the shock-absorbing device is installed only on the front fork, while the rear wheel is rigidly fixed. The presence of a shock absorber somewhat increases the weight of the structure and complicates its maintenance, however, the advantages of such a scheme sig...nificantly outweigh the disadvantages: hard-tails combine good handling, “road feel” and ride comfort, including and on rough terrain.

— Rear fork. Bicycles in which only the rear wheel is damped, while the front wheel is rigidly fixed. The rear shock absorber is designed to provide additional comfort when hitting various bumps, and the absence of a front shock absorber reduces the overall cost of the machine. This option is found mainly in urban models, including electric bicycles (see "Application"); in other varieties, the use of rear shock absorption is not practical.

— Two-suspension (full suspension). Bicycles equipped with shock absorbers on both wheels — a fork in front and a special suspension in the back. Such models are as comfortable as possible for driving on rough terrain, because. They dampen the vibrations felt by the cyclist best and provide the best grip on uneven tracks. At the same time, the presence of a rear shock absorber "eats" part of the energy coming from the pedals, and you have to spend more effort to ride. To avoid this, many two-suspension bikes can be provided with front and rear suspension lockouts (see below), but full suspension complicates the design anyway, increases its weight and price. Therefore, this type of cushioning is relatively rare, mainly in certain varieties of mountain bikes (in particular, for cross-country and freeride; see "Purpose").

Front fork suspension type (if available, see "Suspension"). All shock absorption systems in bicycles work in two directions: vibration damping (damping) and impact energy absorption (cushioning). Accordingly, they have two main components: a damper and a shock absorber. Depending on the design features of these elements, the following types of depreciation are distinguished:

— Spring-elastomer. In this case, the role of a shock absorber is played by an elastic spring, and the role of a damper is played by a rod made of an elastic, well-compressible material, the so-called elastomer. This type appeared as a development of conventional spring damping systems, it is more durable, but poorly suited for low temperatures — the elasticity of the elastomer in such conditions decreases, which negatively affects the characteristics of the system.

— Spring-oil. Systems using a spring as a shock absorber and an oil cartridge as a damper. This design is somewhat more resistant to low temperatures than spring-elastomer, and in general has quite good characteristics, due to which it is quite widely used in various types of bicycles. The main disadvantage is the higher (on average) cost.

— Air-oil. Combined systems consisting of an air cylinder that acts as a shock absorber and an oil cartridge that acts as a damper. They appeared as a developmen...t of “pure” air systems, which had a serious drawback: even with high-quality maintenance, the seals wore out rather quickly, which could disable the shock absorber. Air-oil systems are more durable and easier to maintain, while being quite efficient and weighing little. The latter is especially valuable for cross-country (see "Purpose"), where it is required to combine depreciation with a low weight of the machine.

Front fork travel on bicycles with damped suspension (see "Suspension"). Roughly speaking, the travel of a fork is the maximum distance that its size can be reduced by compression during shock absorption. The longer the fork travel, the better the shock absorption and “soft” ride it provides, but not all bikes require a lot of travel. Even within the same type (see “Purpose”), depending on the specific application and riding style, the optimal fork travel will be different — for example, freeride mountain bikes need good shock absorption, and for cross-country, on the contrary, a long fork travel will be redundant.

In general, if you do not plan on extreme cross-country riding or doing cycling tricks, this parameter is not critical. However, when choosing a bike for serious cycling, it is worth checking the recommended fork travel values (according to specialized literature or from professionals) and making sure that the desired model corresponds to them.

— Aluminium. In this case, aluminium is the simplest and most unpretentious option. Its advantages include light weight; on the other hand, in the absence of shock absorption, the steering wheel with such a fork is highly susceptible to vibrations, and in terms of durability, aluminium is somewhat inferior to steel.

— Steel. Another relatively simple option, which at the same time is considered more advanced than the aluminium described above, and is found even in fairly expensive pro-level bikes. This is due to the fact that steel is noticeably stronger and more durable, as it is not as susceptible to "metal fatigue". However such forks weigh a little more than aluminium ones.

— Chromium molybdenum steel. A type of steel that is more advanced than more traditional grades. Among the main advantages of such alloys are high strength and reliability; at the same time, due to such properties, individual elements of the forks can be made thinner, and the forks themselves can be made lighter than ordinary steel ones. The main disadvantage of Cro-Mo steel is the rather high cost.

— Carbon. Lightweight and high-strength carbon fibre forks effectively dampen small bumps in the road under the wheels of the bike and slightly spring on small potholes, thereby providing cushioning on bumpy roads. The carbon fork facilitates the design of the front of the bike. Most often it is found on board "highways" and "gravel roads", less often it is installed in o...ff-road fatbikes. Vulnerable point — carbon forks break under the influence of strong point impacts.

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 ty...res 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.

Model of the derailleur (derailer) installed on the carriage with pedals as standard on the bike. For more information on why you need to know the model of a particular bicycle component, see paragraph "Cassette Model".

Type of shifters — devices that control gear shifting — installed on a bicycle. To date, the following types of shifters are used:

— Trigger. The design of this type is based on the use of 1 or 2 levers, as well as (sometimes) buttons located in close proximity to the hands of the cyclist. Trigger shifters can have different designs with varying degrees of convenience (usually, this is directly related to the price category of the device), located above or below the steering wheel, however, a number of common features are characteristic of all such models. Their main advantages are the traditional design and comfort when holding the steering wheel — the shifters are located outside the handles (grips) and do not affect convenience. In addition, they are quite simple in design and installation. On the other hand, this type also has a number of disadvantages. Thus, the presence of protruding parts increases the risk of equipment failure or injury to the cyclist in an accident. In many models, especially the low-cost level, in some cases, you have to take your hand off the steering wheel to change gear, which can lead to loss of control. In addition, shifting gears more than 2-3 "clicks" per press in trigger shifters is somewhat difficult and requires skill. However, in most cases, these disadvantages do not play a decisive role, and this type of levers is by far the most popular.

— Grip shift. By design, the grip shift is somewhat reminiscent of motorcyc...le gas regulators: part of the handle is made movable, and gear shifting is carried out by turning it in one direction or another. Since the grip shift rings are actually combined with handles (grips), you don’t need to remove your hand from the steering wheel to control the gears — just move it a little to the side, and you can switch speed (and in some cases you can even keep your hands on the rings all the time). Such systems are devoid of protruding parts, which increases reliability and safety. Another advantage over triggers is the ease of shifting gears to any number of speeds. The main disadvantage of this type is the increased risk of accidentally shifting gears on a difficult section of the track, when you have to hold on tightly to the grips (especially with large palms and short grips) — you can accidentally turn the shifter, which is fraught with a sharp shift, breaking the chain from the sprockets and loss of controllability. In addition, contact with water or dirt on the ring can lead to slippage of the hand when working with gears, and the rings themselves increase the dimensions of the steering wheel and for some may cause inconvenience in the grip.

— Dual control. An original system that combines the control of brakes and gears in one lever — the brake lever. In this case, braking is carried out by moving towards you, and gear shifting is carried out by shifting up or down. The advantages of such a system are the constancy of the grip of the steering wheel — 2 fingers are enough to control both the brakes and the gears. At the same time, dual control shifters are quite complex in design, as a result, they are expensive and poorly compatible with “non-native” brakes and switches. And the ergonomics of such systems is very ambiguous, ease of use largely depends on the individual tastes of the cyclist. Therefore, this type of shifters is rather uncommon.

— Electronic. The competitive advantages of electronic shifters include the absence of a cable and levers to transfer physical force to the switch. In fact, these are ordinary buttons that send signals to the gearshift control unit. Such shifters work in conjunction with electronic switches that are installed on board advanced bicycle models. They can be placed in any convenient place with quick and comfortable access to the switches.