Bicycle frames: varieties and selection criteria

A bicycle consists of a large number of parts, each of which performs important functions and is irreplaceable. One of these is the frame.

A bicycle frame is like a human skeleton. This rough comparison allows us to visualize the functionality of this important detail. Only this structural element cannot be replaced with a new one.... If it breaks down, you will have to buy a new vehicle.

Also, the bike frame should be light, but this requirement is secondary in importance. Therefore, you should not chase lightness and base your choice of cycling on this indicator. This can lead to choosing a bike with poor ride performance.

A few more points can be added to this list of requirements:

• vibration damping demonstrates the frame's ability to smooth out shocks and reduce operating vibrations;
• The maintainability of the frame enables the user to carry out repairs after the expiration of the warranty period.

Bicycle frames come in a wide variety, but the design is much the same. There is a basic set of structural parts that are found in the structure of almost all frames.

• Front triangle (despite the name, it consists of four pipes, not three) includes:
  • head tube;
  • three tubes: main, upper, seat.
• As for the rear triangle, then its design consists of a set of parts:
  • seatpost;
  • carriage assembly;
  • top and bottom feathers;
  • dropouts are brackets that hold the rear wheel.

Also, any type of frame is equipped with individual elements that are needed to install some specific components:

• the steering column is inserted into the head tube;
• the carriage is placed in a special hole;
• the seat tube, together with the seat, is also inserted into a special hole.

This concept plays an important role in the formation of the main characteristics and functional features of the cycle frame. Geometry is directly related to the shape, dimensions of the pipes, the angles at which they are connected to each other. The most important of these are the following characteristics:

• angles of inclination of the seat tube, as well as the head tube;
• the length of the upper and seat tubes.

Many manufacturers indicate on their models the dimensions that refer to the frame. You need to be guided by these indicators, because it is on them that the choice of any bike should be based:

• Saddle height speaks of the height of the seat, in other words, the distance from the center of the carriage and the midpoint of the saddle;
• Stack - the vertical distance from the center point of the carriage to the uppermost area on the steering column;
• under the concept Reach refers to the horizontal distance that starts at the center point of the carriage and ends at the top of the steering column;
• concept Bottom braket drop can be translated as carriage indentation, which will indicate the degree of underestimation of the center of the carriage in relation to the center of the rear hub;
• under Handlebar drop refers to the rudder offset or vertical difference between the upper extreme points of the saddle and the rudder;
• Saddle seatback indicates the offset of the seat or the horizontal distance of the front point of the saddle from the center of the carriage;
• under Standover height the total height is meant, in other words, it is the distance between the ground and the upper pipe related to the front triangle;
• Front center denotes the gap between the center points of the two components: the carriage and the front hub;
• under the concept Toe overlap refers to the distance from the user's foot on the pedal to the front wheel when turning.

The geometry of the frame structure determines important characteristics of the bike, namely its behavior, stability, steering responsiveness, acceleration, user comfort, braking and, of course, dynamics. Therefore, it is so important to study in detail the basic parameters of the geometry before buying a bicycle.

• Top tube originates at the center of the headset and ends at the center of the seat tube. The stability of transport and its maneuverability depend on this value - with an elongated pipe, transport will behave better on the road.

• Steering well angle (glass) is formed between the desired element and a vertical line located exactly parallel. Increasing this parameter improves the bike's ability to maneuver.

• Seatpost angle is obtained due to its inclination relative to the straight parallel. The shift of the center of gravity, the predisposition of the bike to extreme riding and the quality of grip on the road surface depend on it.

• Wheelbase is determined by the distance between the center points of the two bushings. An increase in the indicator will entail an increase in stability, maneuverability, stability.

• Downstairs The rear triangle typically starts at the center of the BBC and ends at the center of the rear wheel hub. The shorter this length, the higher the strength and reliability of the frame structure. Also, the grip indicators go to a higher level.

• Clearance Is the distance to the bicycle bearing assembly.This indicator has a direct impact on cross-country ability and speed capabilities. With an increase in ground clearance, the bike's behavior becomes more confident, which is important for difficult road conditions. Along with this, the speed indicators are falling, therefore, the "golden mean" is important in this indicator.

• Stem length determines the ability of a bicycle to maneuver, which is important for urban and extreme conditions.

Bicycle frames are made from all sorts of materials, each with its own advantages and disadvantages.

• Steel frame comes in two varieties: made from chrome and molybdenum, or made from structural tensile steel. The first option is more preferable due to the use of butting technology. The chrome-molybdenum pipe turns out to be lighter when compared to similar models made of structural steel. Steel frames look sleek, but corrosion is their biggest problem. It is easily solved by keeping the paintwork in good condition.

• Aluminum frame varieties are not made from pure aluminum, because it is very soft. To increase the strength characteristics, silicon, zinc can be added to it. By the first digit of the alloy designation, you can find out about the base metal, which is also called alloying. In the 5000 series, the reinforcement is achieved by magnesium, in the 6000 series, by silicon. Compounds 7000 are based on aluminum and zinc, magnesium is present in small amounts. Raw materials with a large amount of magnesium are most susceptible to corrosion. The main disadvantage of aluminum structures is the ability to accumulate fatigue deformations. Because of this, welds and contact joints are weakened.

• Titanium construction stands out for its long service life. Its strength is on par with steel frames. The main advantage is its high resistance to corrosion. It is difficult to work with titanium structures, because such frames are distinguished by an impressive cost. Such parts are commonly found on expensive sports bikes, which are selected by professionals. Not every novice athlete or just an amateur can afford such a purchase.

• Carbon bike frame created from a multicomponent material where thermosetting resins and carbon fibers are present. Only in carbon fiber can the stiffness be changed in the desired direction. Even at the production stage, the direction in which the carbon threads will be weaved is chosen: it can be transverse or longitudinal. The strength of the product depends on the amount of resin between the carbon "matter": the more it is, the lower the indicator will be. During overloads, the fragile resin is primarily destroyed, only then the threads suffer.

Carbon fiber frames are available in two versions: composite and monocoque. In the first case, the structure is assembled from separate parts. The second option is more reliable, since the frame is solid.

• Magnesium frames - this is a great rarity, because this material is expensive. There is no lighter frame yet. Such structures perfectly reduce vibrations, but they turn out to be powerless before pinpoint impacts. Also, magnesium is afraid of corrosion and exposure to aggressive environments. Magnesium is absolutely not suitable for cycling tourism, since heavy loads are detrimental to frames of this type.

• Chrome frame weighs more than aluminum. But this material lends itself well to repair. Chromol also perfectly dampens vibrations.

All existing frames, which are the backbone of bicycles, fall into two broad categories.

• Female species can have a slightly lowered upper tube, or they can be produced without it at all. When creating such structures, the characteristics of the female body are taken into account, therefore they are the most convenient and comfortable option for cyclists.
• Men's frames - these are constructions familiar to everyone, without any obvious differences. They are more common.

Off-road bike frames are divided into the following types:

• at the hardtail there are no rear suspensions, as well as rear shock absorbers, so this design is ideal for MTB (mountain bike);
• soft-tail it is designed for off-road vehicles with a pair of shock-absorbing devices, this type of frame is not designed for jumping, but it copes perfectly with hilly roads;
• double-suspended version with a rear shock absorber is designed for active driving, installation of a trunk is not provided;
• tandem off-road frame Allows for wide tires and suspension forks to be fitted to the bike.

Road structures are produced in the following varieties:

• classic version designed for a city bike, has a vertical seat arrangement, allows you to install a trunk;
• road bike frame characterized by excellent aerodynamics and dynamic coasting, developed for low landings, there are no fastenings for the trunk;
• rigid Available for bicycles without shock absorbers that can be used on an extremely flat road for hard riding;
• cyclocross needed to perform maneuvers, as well as to drive on uneven roads;
• bicycle frames touring - the best option for long arrivals and travels, they have a streamlined design and are distinguished by a high level of comfort, it is possible to install two trunks at once;
• tandem frames are designed for two-seater bicycles.

Deserve special attention folding bike frames. Most of them are characterized by their small size and the presence of a hinge in the middle of the pipe. Some models are equipped with a telescopic mechanism that makes it easy to extend / fold the handlebar and saddle.

• Stark - it is one of the most affordable brands to look at. This is not just another Chinese firm with low-quality fakes, but a promising manufacturer with big ambitions and plans for the future. Trial frames stand out from the presented assortment.

• Atom Is a Russian manufacturer that offers affordable bicycles of good quality.

• Merida not all cyclists respect it, but there was still a place for it in our rating. It was in this production that lightweight magnesium alloy frames began to be produced, which were offered at an affordable cost. The bicycles of this company are characterized by an optimal ratio of cost and quality.

• Author Is the most promising company in our ranking. The XC frames deserve attention. They are rolling and moderately tough, therefore they are equally suitable not only for races, but also for marathons and tourism.

• Scott Is an American company that enjoys high popularity in the world market, not to mention the national one. The assortment consists of many models, among which each user can choose the desired option.

• Gary fisher is the most famous company in the world bicycle market. An industry giant in which it has proven itself exclusively on the positive side. This company owns a large number of brands. High quality, decent performance, innovation, exceptional performance - what else does a cyclist want?

• Trek is a worthy competitor to the previous manufacturer.It has earned high recognition among Russian users. Many models from entry to professional level, with sturdy frames that are created from innovative alloys.

The frame is selected based on two important criteria.

1. User growth. For a person with a short stature (from 155 to 162 cm), a frame with size XS (51 cm) is more suitable. Just add a few cm to the frame length and it will be designed for users between 162 and 170 cm in height.Cyclists up to 182 cm should look at frames in size M. The L design is suitable for people up to 192 cm. the XL frame will be convenient for cyclists taller than 192 cm. If the model is chosen for a risky ride, then the frame should be chosen smaller than indicated above. This secret will allow you to get more manageable and maneuverable transport.
2. Weight also needs to be considered... Typically, larger frames have increased strength, which is achieved by increasing the thickness of the material. Overweight users should look at models with a reinforced frame, which will be characterized by a larger diameter, stronger alloy and thicker walls.

For information on how to choose the material of the bike frame, see the next video.