The Bike

The Bike

Hardtail: lighter in weight and more affordable; requires less maintenance and allows for direct power transmission:

     Racing-, touring-, dirt- and trial bike
 

Fully: dual suspension; better traction, more comfort, more health-conscious, fun and safety:

     Racing-, marathon-, all-mountain-, enduro-, freeride- and downhill bike

 

Frame Materials

Steel: This material is still being used for children and youth bikes in order to achieve/offer competitive prices

 

Aluminium: The number-one material in the construction of mountain bike frames, especially for Fullies, this metal is processed in various alloys. Alu 6061 or 7000 are among the premium types. A “T” in the name stands for “Heat Treated”. In order for the aluminium to be durable and resistant it needs to be heat-treated.

 

Carbon: This material used to be somewhat exotic and only used for the production of small batches but is now a standard feature and used in mass production. Brands like Trek, Giant, GT, Simplon, Scott and Merida were at the forefront of introducing carbon for their frames. The applied geometrics and the used materials are manifold – and they remain any developer’s well-kept secret. Main benefits of carbon are weight, elasticity and antishock properties. A stronger torsion, especially in terms of steering head and bottom bracket, is seen as a disadvantage.

 

Titan: This is a premium material for Hardtails, but too expensive for the majority of riders. The benefits are in no relation to the costs.

 
Brakes

Hydraulic Disc Brakes: Advantages: requires less hand work, allows for precise control – depending on model, no rim wear, low in maintenance, brake pads are easy to replace; Disadvantages: often increased rubber wear (if skidding), expensive brake pads, heavier in weight, squeaking in wet conditions, not suitable for all frames, repairs and bleeding time-consuming.

 

Hydraulic Rim Brakes: Advantages: increased braking force, great control, easy to replace brake pads, different brake pads available, low in maintenance, reliable; Disadvantages: pressure point not precisely palpable (not ideal for beginners), relatively expensive, elaborate repairs, heavier in weight.

 

V-Brakes: Advantages: strong braking force, affordable, adjustable pressure point, relatively easy to control, tuning brake pads available; Disadvantages: Decreasing brake impact in wet and cold weather, increased rim wear, at times strong squeaking, requires specific levers, more suitabley for road racing bikes!

 
Suspension

Suspension fork and shocks absorb impact while cycling and thus reduce strain on the cyclist, while at the same time allowing for better traction as the wheels roll over obstacles instead of being lifting. Efficieny and traction always depend on the respective settings.

In order for fork and shocks to react perfectly and to compensate potholes and make use of the spring deflection, the rebound needs to work. What good is a 120mm spring deflection if you only use 80mm? The correct tractive level determines whether the fork reacts ideally to the surface conditions. The pressure level regulates the compensation speed. If the settings are ideally adjusted you can avoid having to rock forwards and backwards while still allowing for finely tuned reactions.

 

Suspension forks accomplish great results: They transfer steering forces and absorb side-, torsion- and braking forces. Their dilemma: The market asks for ever-decreasing weight and increasing stiffness as well as finely tuned forks and pedals that require as little rocking as possible in order to offer the highest-possible protection. Stiffness and weight cannot be manipulated once the fork has been purchased – but the set-up and therefore the performance can be!

 

Numerous setting options influence the fork’s performance properties. From no reaction to the conditions and a bouncy fork to slow reaction with plunging travel, anything is possible –the ideal case would be somewhere in the middle. You can determine the exact position of your personal ideal case with only a few adjustments. First find the right sag to allow for an optimal fork travel as well as ideal rebound. Once you have optimised rebound and compression, the suspension will react at the right speed.

 

A rear shock has numerous functions. It should react to the merest impact yet at the same time compensate bigger bumps. The wheel should remain on the ground at all times and have enough grip in any bend. When pedalling, the rear should hardly move in order to allow for the majority of the pedalling energy to be transferred into forward motion. The rear wheel must remain in contact throughout the corner to apply grip. The function of a rear shock is more complex than that of a front fork.

 

Kinematics as well as integrated shocks greatly influence performance. That is why frame and shock manufacturers work in close cooperation to finetune the shock- to the rear frame properties. In order for the system to work perfectly, the shocks need to be adjusted individually by the cyclist. As with the fork, rebound as well as compression and air pressure levels require ideal adjustment, so don’t save any time or effort in your tuning.

 

Air Spring: This is the positive air chamber compressed in the fork by using the same principle as steel springs and elastomers. The air pressure can be adjusted to the cyclist’s weight with the use of a special high-pressure pump.

 

Dampers: Their function is to reduce bumps. In suspension forks, the shock system regulates the deflecting and straightening speed, mostly by having oil run through a tiny opening and transforming energy into heat.

 

Rebound: Each spring tries to release the saved energy after compressing. The rebound regulates the fork’s straightening speed and prevents unwanted excess popping.

 

Pressure Compression: Works in parallel to the air spring and decelerates the fork’s plunge speed. This increases the momentum while preventing the fork to break out rapidly. However, increased momentum will always inmpact the speed of reaction.

 

Sag/Negative Spring Travel: Describes the fork’s plunge course during static pressure by the cyclist (while sitting in the saddle). It is called negative spring travel as it describes the course that can be straightened by the fork in case of potholes and other obstacles. The wheel remains on the ground and makes sure there is no loss of traction.

 

Lockout: This is a lever that can be operated either on the spring or the handlebar in order to block the system and is often combined with a blow-off valve, which releases the spring deflection in case of overload and prevents damages to the spring element.

 

Ideal Spring Deflection: Many cyclists only use a part of the fork travel as their fork and rear shock have the wrong air pressure, which can have dire consequences: The bigger the spring deflection under consistent impact load, the lower the strain on the cyclist. Via the points of contact, the fork channels this force to the handlebar, which as a consequence means a load relief on the cyclist. This is why you should adjust your air pressure so that the fork and rear shock make use of their full travel.

Very important: Take your time in adjusting your bike and try new settings according to the motto: Fitting by trying …