Comparison Author Unica 26 2019 frame 16 vs Author Vectra 26 2019 frame 16

— Steel. Steel is distinguished by high strength and rigidity, in terms of resistance to deformation, it noticeably surpasses other alloys and is inferior only to carbon fiber. At the same time, such frames dampen vibrations well, are inexpensive, and in the event of a breakdown, they are easily repaired. On the other hand, steel is heavy, three times heavier than aluminium and twice as heavy as titanium; therefore, such frames are found mainly among inexpensive mountain and city bikes, for which a lot of weight is not critical. It is also worth considering that this material is susceptible to corrosion if the protective coating is damaged.

— Chromium molybdenum steel(Cro-Mo). An advanced variation of the steel described above. By themselves, chromium-molybdenum alloys have high strength and reliability, and frames made from them can have different wall thicknesses (depending on the load that a particular section is subjected to) — this allows you to slightly reduce weight. Thanks to this, Cro-Mo alloys are found even among fairly advanced road bikes, and they are also popular in touring models. At the same time, such frames cost much more than “ordinary” steel ones.

— Aluminium. Actually, bicycles do not use pure aluminium, but various alloys based on it. They differ somewhat in characteristics, but they have a number of common features, the main of whi...ch is low weight combined with good strength characteristics. Due to this, aluminium alloys are widely used in road bikes, as well as in touring mountain bikes (see “Intended Use”). The main disadvantage of these materials is rigidity: they absorb vibrations worse than steel, which is why they are poorly suited for models without shock absorption (see below), and with a strong impact, such a frame will break rather than bend.

— Carbon. Resin-bonded carbon fiber composite. It is used in high-end bicycles, as it is very expensive, but it is characterized by very high strength combined with low weight. Moreover, the properties of carbon fiber make it possible to increase strength not just in certain areas, but in certain directions, which contributes to even greater reliability. Note that carbon frames can be either solid (monolithic) or composite — in the latter case, individual elements are connected by metal parts, which reduces the cost, but makes the structure susceptible to corrosion. It is also worth considering that the quality of carbon in general depends on the price category of the bike, and relatively inexpensive frames can be sensitive to strong point impacts. This material is almost impossible to repair.

— Titan. A fairly advanced material that combines high strength, elasticity (which provides soft vibration damping), corrosion resistance and very low weight. However, the cost of such frames is quite high, and therefore they are used mainly in premium mountain and road bikes.

— Magnesium alloy. This material is notable primarily for its very low weight (many times lighter than aluminium), while it has good stiffness and elasticity characteristics, dampens vibrations well, and its price is relatively low. At the same time, magnesium alloys have a number of significant drawbacks. In particular, they do not tolerate impacts, especially point impacts, and are also extremely sensitive to corrosion even with minor damage to the protective coating, which is why such frames are very demanding for care and storage.

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.

Varieties of rims are determined by the number of horizontal jumpers in the design.

— Single. The simplest type of rim, similar in cross section to the Latin letter U. It is used mainly in entry-level bicycles.

— Double. Such a rim differs from a single rim by the presence of an additional horizontal bridge. Figuratively speaking, it resembles the same letter U, but with a double bottom. The features of this design are such that it is able to provide increased strength even with less weight than a single one. On the other hand, double rims are more difficult to manufacture and therefore more expensive. They are used primarily in bicycles where high resistance to stress is required — in particular, mountain varieties (see "Intended use") for freeride and cross-country.

— Triple. A further development of the idea of a double rim is a design with two additional horizontal bridges. This provides even greater strength, however, the weight increases quite noticeably. In addition, initially the second jumper was provided to strengthen the side surface, in order to avoid damage during the operation of rim brakes (see "Front brake", "Rear brake"); however, today most powerful brakes are disc brakes, and this problem is losing its relevance. Because triple rims are quite rare.

The number of speeds (gears) provided for in the design of the bicycle. Each transfer has its own so-called gear ratio — in this case it can be described as the number of revolutions that the driven gear (rear, on the wheel) makes in one revolution of the leading gear (associated with the pedals).

Different gear ratios will be optimal for different conditions: for example, high gears provide good speed, but are poorly suited for overcoming obstacles, because. the effort on the pedals increases significantly and the frequency of their rotation decreases. It has been scientifically proven that a cyclist develops maximum power at a cadence of about 80-100 rpm. Thus, the presence in the bike of several speeds allows you to optimally adjust it to different driving modes and features of the tracks in order to provide optimal pedaling force and frequency of their rotation. For example, on smooth asphalt it is best to drive in a high gear, and when overcoming a rise or entering a dirt road, you can lower it in order to effectively overcome resistance.

The number of gears in classic systems is directly related to the number of stars of the system (on the bottom bracket with pedals) and the cassette (on the rear wheel); it can be obtained by multiplying two numbers — for example, 3 stars of the system and 6 on the cassette give 18 gears. However, there is also the so-called planetary hubs — there are stars one at a time, and gear shifting is carried out by a mec...hanism built into the rear hub.

Note that the optimal number of gears depends on the purpose of the bike (see above), and it is not always necessary to have several of them. So, in mountain models, depending on specialization, there can be from 8 to 30 gears, in road ones — within 20-30, and some inexpensive city bikes and most BMXs do not have a gear shift system at all.

The number of stars (gears) of different sizes in a bicycle cassette. A cassette is a part of the rear hub that interacts directly with the chain, in other words, a gear or a set of gears mounted on the hub. In classical gear shifting systems, the number of gears directly depends on the number of stars in the cassette (for more details, see "Speeds"); a single chainring is used either in single speed bikes or in planetary hubs (see System Stars for more on these).

Model of the derailleur (derailer) installed on the rear wheel cassette 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.

The model of the shifters (see “Shifter type”) that are fitted to the bike as standard. For more information on why you need to know the model of a particular bicycle component, see paragraph "Cassette Model".

Model of the chain supplied as standard with the bike. For details on the value of the Model parameter for any part, see Cassette Model