What different types of bicycles are available and what is important for the selection?
Three steps to a back-friendly bike
1st step: choosing the right type of bike and frame sizeThe retailer must offer a sufficiently broad fleet of bikes for test-riding, including city bikes, trekking bikes, mountain bikes, racing bikes, recumbent bikes or even folding bikes. The range on offer should include at least different city and trekking bikes. There are many different types and names of bikes on the market. There are also various mixed forms so that boundaries often become fuzzy.
- The most important types of bicycle are explained below.
- City bikes are relatively heavy and are equipped with or without gears. They permit comfortable cycling in town in an upright position. The upright position tends to prevent the bikes from being used for long journeys. City bikes can carry relatively high loads and only rarely have derailleur gears. Dutch bikes are a special type of city bike and are designed among others with a closed chain case.
- Trekking bikes, also called cross bikes or ATB (all terrain bikes) can be simply described as a combination of racing bike and mountain bike and come fully equipped with all features needed for cycling on the road (luggage rack, lights, mudguards and stand). These bikes are intended for general mobility in town and on tours. The tyres are broader and with a deeper profile than racing bikes, but much narrower than mountain bikes. Trekking bikes are usually equipped with luggage racks – but are not as stable under full load as touring bikes.
- Touring bikes are specially made for cycling tours. In appearance they look like a mixture of racing and trekking bike. They are equipped with sturdy, durable parts and designed to carry heavy loads. They are designed for more moderate cycling behaviour.
- Mountain bikes (MTB) offer a compact and robust design for sporty cycling on unsurfaced paths and open terrain. Many different subcategories of mountain bike have emerged in recent years, with varying wheel sizes, tyre widths and suspension types.
- Racing bikes are used for road racing and for covering long distances at high speed.
- The frame geometry
- Frame and seat height
The frame height (stated in centimetres or inches) is measured between the middle of the pedal crank bearing and the upper edge of the seat tube. The correct seat height indicates the distance from the upper edge of the saddle to the lowest position of the pedal that can still just be reached with the heel. Correct adjustment of the seat height is a basic prerequisite for fatigue-free cycling. Cycling with the seat height too low will sap energy and can cause knee problems.
- Frame and seat length
The effective length of the frame is the horizontal distance between the middle of the seat tube upper edge and the middle of the head tube that takes the steer tube. This length dictates the seat length, i.e. the distance between saddle and handlebars. The correct seat length permits the cyclist to stretch the spinal column in its natural double-S shape when sitting leaning forward slightly (max. 30 degrees). This is the only way for the back muscles to hold the upper part of the body and reduce the pressure on hands and arms. If the frame is too long or too short, the required sitting position won't be possible, not even with stems of different lengths or by adjusting the saddle. In addition to ergonomic aspects, the frame length also influences performance dynamics.
- Stack and reach: new parameters for selecting frame size
According to the bicycle experts, frame height is now obsolete as a reference size. Today it is stack and reach that tell you whether a frame has the right size. Stack and reach refer to the distance between the middle of the pedal crank bearing and the upper edge of the seat tube. Stack is the vertical distance, i.e. the height. Reach is the horizontal distance, i.e. the length. Bikes with more stack and less reach are higher and shorter. The cyclist sits in a more upright position, while less stack and more reach results in the cyclist bending forwards in a more stretched position.
- Frame and seat height
- The most important types of bicycle are explained below.
2nd step: "bike fitting" – individual adjustment of the selected bicycle typeSelection of bicycle type and frame size is followed by "bike fitting", i.e. individual fine tuning of the components.
The sitting position and handlebar shape need to be adjusted to each other. The handlebar should be ergonomically curbed so that the lower arms and wrists can be held in a straight line. The flatter and more stretched the cyclist's sitting position, the straighter the handlebars may be. Straight handlebars make sense for sporty bikes. They support direct steering but put a higher load on the muscles in the arms and shoulders. Make sure that the wrists are not bent when grasping the handlebars as this could cause incorrect loads. Handlebars with differing grip positions are therefore recommended for long journeys. For sporting cycling, the handlebar is lower than the saddle, but above the saddle when cycling for pleasure. The width of the handlebars should be the same as the width of the shoulders and be adapted to the cycling purpose. Basically, the handlebars are only correctly positioned when there is a certain pretension in the back muscles. This pretension stabilises the spinal column and protects it from excess loads. An extremely upright "Dutch bike" position with the handlebars and grips close to the body tends to put more strain on the back.
- Handlebar stem
The handlebar stem is the element connecting steer tube and handlebars. Adjusting the stem angle changes both the distance between the cyclists body and the handlebars and also the handlebar height.
Grip tips: for detailed information about bicycle grips, visit our site about Grips
• Anatomically shaped grips with damping characteristics help reduce impacts and pressure on the nerve roots. (The ulnar nerve is close below the surface of the skin in the area of the hypothenar muscles. It is very sensitive to pressure loads in this location.)
• A large supporting surface is ideal in order to minimise the pressure and possible numbness in the ring finger and little finger.
• Specially shaped, multi-position handlebars and grips with bar ends enable various hand and grip positions, counteracting rapid fatigue of the arms and wrists as well as tense muscles in the shoulder and neck area.
Saddle tips: for detailed information, visit our site about saddles
• The retailer should offer saddles and seat posts in a range of varieties.
• The seat should have a relief zone in the area of the perineum and genitals in order to facilitate a back-friendly pelvis position on the seat (maintaining the lordosis in the area of the lumbar spine).
• The saddle must be selected individually (shape, size, hardness) and the position adjusted correctly (height, tilt, length position).
• It is also advisable to measure the sitting bones when selecting the right saddle.
3rd step: individual suspension/shock absorptionThe suspension reduces shocks and jolts caused by uneven road surfaces. The German Sport University in Cologne has investigated the impact of suspension systems on the spinal column and came to the conclusion that jolts are reduced by 35% in bicycles with full suspension. This protects the spinal column from critical shock loads. Full suspension also protects the cyclist's entire locomotor system, as well as improving safety aspects.
The retailer should offer solutions that permit individual suspension/shock absorption.
There are various suspension systems:
- Suspension fork adjusted to bodyweight
- Suspension in the seat post or direct with full-surface dampers in the seat
- Rear wheel suspension adjusted to bodyweight
- Full suspension (suspension fork and rear wheel suspension)
Requirements for the suspension/shock absorption of a bicycle:
- The spring kinematics must warrant low reciprocal effects between drive and suspension.
- Any luggage must also be suspended and therefore fastened to the frame. The load carried on the bike may not impair the suspension functionality and safety aspects (weight distribution).
- Attention should also be paid to selecting special tyres with adjustable tyre pressure to take account of performance dynamics.