Bicycle rollers

As a freelance role, also free, unrestrained role or (English and as product name) Rollertrack is called a training tool in cycling for the simulation of cycling without having to move it from the spot. Expressions such as training role and the role coaches who were once synonyms for the free role, by contrast, used today as a generic term for various devices, especially those with a locking of the bicycle.

The free roller consists of three metal or plastic rollers of about 50 cm in width, which are installed in such a manner to rotate freely in a metal frame that it excepted Road with the rear wheel securely between the two rear wheels and with the front just behind the front roller space place (see pictures). In contrast to the usual practice today roll the bicycle is not fastened, only positioned and keeps a dynamic equilibrium due to the centrifugal forces of the rotating wheels, and the driver's steering movements.

Types of training wheels and bicycle ergometers

The free role is only one type of sports equipment with which the cycling is simulated. The following units are used:

• Fitness ergometer with and without flywheel and with different braking devices
• Ergometer as scientifically sound tests with and without flywheel and with different braking devices
• Spinning bikes with a flywheel and brake assembly
• The free roller with and without braking device and without significant Inertia
• Training roles with attachment point for the bike with different braking devices.

Technical features of the free roller

The driver along with the bike is held upright on the free roller due to the centrifugal forces. This requires a minimum speed of 20 km / h or about 160 impeller revolutions per minute. To raise the necessary centrifugal forces and to make the bike controllable, the rotation is transmitted through a V-belt from the front of the two rear rollers to the front roller. The front roller so enables the front wheel to rotate, so that it exerts its stabilizing gyroscopic forces. Feet on the frame of the roller thereby cause footing and prevent accidental braking of roles by dragging on the ground.

Braking devices on a free role are rather uncommon, but available. By braking devices driving is probably so slow on the free role that the above minimum critical speed is exceeded.

Skill of the driver

Since the dynamic stabilization forces that occur in the free role unlike the drive fail, on road and track different, the taxes on the free roller requires some getting used to. Overall, the driver is with the wheel in an unstable condition, the wheel reacts to steering movements nervous, mainly because the stabilizing effect of the wake is missing.

Functions of the free role in training

Because of the higher skill applied the free role is initially used as a means to support the driving technique. It is often carried out at high cadence. At the same time, therefore, serves the role of the free training of the circular passage. However, should the paramount importance, mainly as a training medium in track cycling had a free role until well into the 80s, to be qualified. On the one hand and low cadence high power use their positive effects on the " pedaling " have, on the other hand is the most important feature both free rolls as well as the distributors of such optional mounting for the bike missing in motion, inertial mass ( system weight of the bicycle and rider or flywheel like the spinning bike ).

By eliminating the flywheel, the driver is in the free role does not have the irregularities in the development of power " helped away " - he must himself be addressed by improving muscle coordination.

The free role contributes mainly to the development of the circular passage, - if driven with a fixed gear on it - as usual in track cycling. The lack of free-wheeling the bike namely reacts with irregular steps with a flyout forward and reverse commuting, what a destabilizing force already at medium cadence and the driver stops for better pedaling technique.

Another function of the free roller is given in track cycling by the fact that the driver can not warm up on the track ( there usually run other competitions). But for this purpose the free roller is gradually replaced by rollers with mounting and braking device.

Advantages and disadvantages of the free roller

Disadvantage of the independent role as well as almost all types of wheel fixing is the lack of a flywheel. While this workout from methodological reasons (see above) can be an advantage even, it is felt by the driver rather than a lack of realism. Further, a driving standing almost impossible in the free roller.

The free role has its advantages clearly in reasonably realistic simulation of high-frequency stepping on the train, which is why she was even there displaces the least of the role of attachment. When training the maximum cadence in compliance with the driving line it is still for sprinters almost indispensable today. Sprinters should reach on this device, crossover frequencies between 220 and 250 rpm (for comparison, street amateurs typically reach maximum frequencies of 170 to 200/min ).