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How to Choose the Correct Bike Type and Size?

Do you want to buy a new bike but are not sure how to choose the correct size and model or accessories? We prepared a thorough guide to help you.

Considerations Before Buying a Bike

Before buying a bike, there are several aspects to consider. The first step is to choose the type of the bike, which depends on the terrain you plan to use the biike on. From this perspective, there is no all-purpose bicycle. Each bike is suited to different kind of terrain and it is important to consider the future use of your bike carefully. The chosen bike model, rpice and quality should reflect your riding style, expected mileage and predominant terrain on which you plan to ride.

When choosing a bike, take into consideration:

Choosing the wrong frame size or adjusting the seat post incorrectly can significantly decrease your comfort during the ride and cause back pain and other problems in the long run.

How to Choose the Type?

Frequent terrain rides
In this case, a mountain bike is the ideal choice. Mountain bikes have wider tires and rougher pattern which makes it easier for the wheels to adhere to slippery surfaces and keep balance on uneven terrain. You can divide mountain bikes into two categories – bikes with fixed frame and suspension bikeswhich have both suspension fork and suspension frame. Thanks to these features, the user can pedal evenly on unstable terrain and handle riding down difficult slopes. Some suspension bike models have the option of locking both the front and the rear suspension, which is an advantage cyclist who want to ride both in rough terrain and less difficult conditions surely appreciate.

Regular recreational and urban rides
An urban bike, suited for riding on hard flat surfaces, is more than enough for such purposes. Another choice for recreational rides is a trekking bike, equipped with such features as mud guards, lights, a bell or a carrier.

Regular long-distance road rides
A road bike is the correct choice in this case. Road bikes are designed to have an aerodynamic frame, minimal resistance and a prefect force transference. The bikes have only necessary components and their gear shifting is focussed on speed. They are the lightest of all bike types.

Combination of terrain, urban and road rides
In this case you can compromise with a cross bike or a trekking bike. Cross bikes combine the advantages of road and mountain bikes. The seat is more vertical, the wheels have a bigger diameter (28) and the tire pattern is more universal for more sped on tarmac surfaces. If you plan on riding on less difficult terrain, this bike is an optimal choice for you.

Other specialized bikes
Folding bikes, E-bikes, BMX, children’s bikes.
 

How to choose the wheel diameter?

The most important is choosing the right type and size of your bike and your riding style, technique, the environment or the terrain in which you will ride, as well as the height of the person. Let's mention that there is no single, universal right size - all have their advantages and disadvantages. You can´t choose size when buying cross and tracking bikes cross and tracking, these bikes has size 28", but mountaunt bikes mountain bikes has sizes 26", 27,5" and 29". Also citi bikes has two sizes city bikes 26" and 28". When buying children bikes children bike the height of the kid is important.

Advantages of bigger bikes:

  • thanks to the larger diameter of the wheels, it is better to ride over rocks and roots
  • a longer distance travels on one step, the wheel is faster
  • a larger tire volume provides more comfort
  • due to the center of the wheel is the lower center of gravity, which provides greater stability
  • a larger footprint (the area the casing touches the ground) means better grip

Advantages of smaller bikes:

  • smaller wheels mean lower weight - less power is needed to start, acceleration is better
  • better maneuverability on narrow and frequent turning paths or in heavy traffic
  • more suitable for riders that are less than 165 cm in terms of optimum geometry of the frame
  • the ride is more playful, more vivid and fun

Frame material:

Frames are made of variety of materials - aluminium, magnesium, scandium, carbon, steel and in rare cases titan. The following table offers basic information about the properties of the materials:

Aluminium – The advantage of aluminium alloys is light weight and side frame rigidity. Their disadvantages are low to none flexibility and higher price when compared to steel frames. An important factor influencing the properties of aluminium frames is tube shaping. Aluminium frames are marked alu (possibly with designation 6061, 7005, 7020 etc.), allux, alloy, dural, easton, alutron, etc. The price and weight of these frames depends on the type of aluminium alloy and the method used to produce them.

Carbon – Carbon is made when layers of carbon fabric and glue are moulded under pressure in a vacuum. This method enables the manufacturer to add material where necessary and reduce its amount when not. That’s why the material is at once extremely durable and light. Since the method was perfected, carbon frames have become the number one option for bicycles.

Steel (Hi-Ten) – The advantage of steel frames is their flexibility and low price. However, they are rather heavy. To compensate, steel alloys are used instead, such as Cr-Mo (ameliorated steel with added chrome and molybdenum) or Columbus. Thanks to the alloys’ durability the tubes can be thinner and that makes the frame lighter. The price rises with the quality of the alloy used. Steel is most often used to make BMX frames to ensure durability and impact resistance.

Frame advantages

Aluminium Carbon Steel (Hi-Ten)
 + light weight  + durability  + rigidity
 + rigidity  + extremely light weight  + flexibility
     + high-quality production

kolo

How to Choose the Correct Frame Size?

Frame size (height) is defined as the distance between central axis and the end of the seat tube. Frame size is usually determined in inches (1 inch = 2.54 cm). Frame size of a bike can slightly differ, depending on the brand or frame type. When choosing a bike frame, we recommend taking into account also the length of the user’s legs (third table below). Cross and trekking bike frames can be 1 – 2 inches higher.

Frame size according to the user’s height (adults)

User height Mountain bikes (inches) Cross bikes (inches) Road bikes (cm)
 150 - 155 cm  15" - 16"  16"  50 - 52
 155 - 160 cm  16"  16"  52
 160 - 165 cm  16" - 17"  17"  52
 165 - 170 cm  17" - 18"  17" - 18"  52 - 54
 170 - 175 cm  18" - 19"  18" - 19"  54 - 56
 175 - 180 cm  19" - 20"  19" - 20"  56 - 58
 180 - 185 cm  20" - 21"   20" - 21"  58 - 60
 185 - 190 cm  21" - 22"  21" - 22"  60
 190 - 195 cm  22" - 23"  22" - 23"   62
 195 +  23" +  24"  62 - 64


Frame size according to children's height:

Wheel diameter Child's age Child's height (cm)
 12"  2 - 4     90 - 110 cm 
 14"  3 - 5     95 - 115 cm 
 16"  4 - 7   100 - 125 cm
 20"  6 - 9  105 - 135 cm
 24"  8 - 12  115 - 155 cm
 26"  10 +  155 cm +


Frame size according to user’s leg length (adults)
Frame size is determined by the length of the seat tube and the seat tube length determines all the other frame dimensions. This size is called “centre-centre”. The general recommendation for choosing mountain bike frame is to have a 5 cm gap between the horizontal frame tube and the user’s groin while standing above the bike. You’ll find recommended frame sizes in the table below. User height is included for illustration purposes.

User height Leg length Frame size
Sports use Recreational use
 161 cm  72 cm  40 cm  15,7"    42 cm  16,5"
 165 cm  75 cm  42 cm  16,5"  44 cm  17,3" 
 169 cm  79 cm  44 cm  17,3"  46 cm  18,1"
 173 cm  82 cm  46 cm  18,1"  48 cm  18,9"
 179 cm  87 cm  48 cm  18,9"  50 cm  19,7"
 183 cm  89 cm  50 cm  19,7"  52 cm  20,5"
 187 cm  92 cm  52 cm  20,5"  54 cm  21,3"
 193 cm  96 cm  54 cm  21,3"  56 cm  22"

Components Set

The components set includes various bicycle parts. These are brakes, stems, pedals, gear shifting, seat posts, cranks, derailleurs, etc. It is best to have a complete components set, without mixing brands or levels. Basically, the higher the quality of the components materials, the higher reliability, adjustability, longevity and also price. The cheapest components are usually made of moulded metal plates or plastic. The more advanced components are mainly made of scandium, titan and carbon. Expensive high-quality components also weight less, which is especially advantageous for longer rides.

Brakes

Brakes are the main safety feature. However, they differ in their function and efficiency:

V-Brakes/Caliper Brakes - This system uses cable-controlled rubber pads that are pressed onto the wheel rims. The advantages of this type of brakes are easy maintenance, low cost and overall simplicity of the system. On the other hand, the disadvantage is that braking efficiency is reduced when riding on wet surfaces.

Coaster brake/Back pedal brake - This is a type of a drum brake that is responsive to the reverse movement of the cranks. Because of its low price, it can be found mainly on urban or children's bicycles that are not usually used for longer rides. The disadvantages of the coaster brake are low efficiency and poor cooling. However, under normal conditions, it will last for a very long time without any maintenance needed, and it is resistant to mud and water, damage to the axis or even rough handling.

Mechanical Disc Brakes - These brakes use brake pads to put pressure on the disc mounted at the centre of the wheel. In this case, the force from the brake levers is transmitted by the cable. The main advantage of mechanical disc brakes is their high braking efficiency. The disadvantage is their low sensitivity for varying strength levels and susceptibility to damage.

Hydraulic Disc Brakes - Unlike mechanical disc brakes, hydraulic brakes use brake fluid pressure. The main result is high efficiency (even higher than with mechanical disc brakes) and intuitively sensitive control. That's why they appeal to more demanding users that brake frequently (i.e. on long rides downhill) or heavier cyclists (when higher braking effect compensates for greater wheel inertia). The disadvantages are again susceptibility to damage, higher price, a risk of leakage and more complex servicing.

Fork

Forks, especially those with suspension are increase driving comfort. However, it differs in several parameters that should be considered:

Material - affects practically the same characteristics as frame

Fork lift - determines the extent to which the fork can flex

  • without suspension - These forks are used on road and city bikes where riding on a high-quality paved surface is assumed, or on cheaper bikes
  • 40-64 mm - ideal for urban, trekking and crossbikes, that are used mostly in lighter terrain or on poor road quality (for example, pavement, field roads, partially paved forest roads etc.)
  • 65-80 mm - ideal for mountain and cross bikes in unpretentious mountain terrain (forest paths, simple trails etc.)
  • 81-100 mm - ideal for mountain to more demanding mountain terrain (forest roads and beyond, roots, rough stones, moderate trails etc.)
  • more than 100 mm - they are mainly used in all-suspension bikes that are suitable for very heavy terrain, especially for users of more professional enduro and freeride use

Suspension type, lockability, damping adjustment - zou can choose from wide range of heavy-duty spring forks without the possibility of locking and regulation to light duralumin, titanium or composite with air spring, damping control, rebound and also locking when the suspension fork becomes unsprang – so-called lock out - from handlebars. This can be displayed in abbreviations or labels that are usually after the name of the fork. We will therefore show you some of them:

  • LO - lockable fork (controlled on fork, some manufacturers use term, for Speed Lockout, which means that there is no need for tools) (LOCK OUT)
  • LOD - lockable fork with suspension adjustment (control on fork) (LOCK OUT + DAMPING ADJUST)
  • ELD - electronically lockable fork with suspension adjustment (control on fork) (ELECTRONICAL LOCK OUT + DAMPING ADJUST)
  • MLO - mechanically lockable fork (control on fork) (MECHANICAL LOCK OUT)
  • HLO - hydraulically lockable fork (control on fork) (HYDRAULIC LOCK OUT)
  • RL / RLO - remote lock on the handlebars (not on fork) (REMOTE LOCK OUT)
  • RLD - remote lock on the handlebars (not on fork) with suspension adjustment (REMOTE LOCK OUT + DAMPING ADJUST)
  • TAD - adjustable height and suspension (TRAVEL ADJUST + DAMPING ADJUST)
  • TR - adjustable height and remote handlebar lock of the fork (not on fork) (TRAVEL ADJUST + REMOTE LOCK OUT)
  • AIR - air fork - the hardness is regulated by the air pressure in the fork and adjusts to the use of the rider (AIR SPRING)
  • D - the spring fork – the suspension is provided by the spring (COIL SPRING)

Naturally Ergonomic Saddle Position

Adjust the saddle to the correct height. Step on one of the pedals and bring it to its lowest position. You should be able to reach the pedal with your heel. While riding, the tip of your foot should be on the pedal and your leg should be slightly bent at the knee while in the lowest position. Under no circumstances should your hip bones move from side to side. Your hip area should be practically immobile. Seat inclination is adjusted according to the rider’s needs or the bike type. A horizontal position is ideal for mountain, cross and road bikes.