What body, a bicycle

2002/07/28 Kortabarria Olabarria, Beñardo - Elhuyar Zientzia

• Diseinua
• Teknologia

Custom bikes allow you to take advantage of strength.

A young man enters the bicycle shop. With the delivery of the good morning, the seller asks:

- And what do you need?

The child responds that he wants to buy the bike, that he intends to take out the federated card and start racing. Both have been talking. Cycling is hard and to see if you have thought it right, that you know it, but that nobody turns you off in the village and that a former cyclist has encouraged you to do it; that he is glad that the young man looks so lively because every time he appears less young with that type of intention and how much he wants to spend; that although last summer he has worked in a bar and has saved money…

In addition to the bikes in the store, they have been aware of the ones in the catalogs until they have chosen the frame and the rest of the components of the bike. Then the questions become sellers again:

- Do you want to make it custom?

Yes, you would like it but you may not have enough money for it. The seller tells you that the bikes made are a little more expensive, 5%, but to be calm, this time will not charge you, they will celebrate it when you win the first race.

Both the bicycle and the body are taken into account in the construction of custom bikes.

- See, let's start taking action. You must remove the first shoes.

Physically all people are different. The height, the length of the legs, arms, trunk... are aspects to take into account when taking advantage of force or go more comfortably on the bike.

The seller begins to take action on the young man. The boy, standing empty, leaning on the wall, measures his leg first. Multiplying the distance from the crotch to the ground by the coefficient 0.65, which varies according to the type of bicycle, gives the height (A) of the frame, that is, the distance of the bottom bracket to the base of the chair. He then took measurements from the leg to the shoulder. Multiplying these measurements by the coefficient 0,888, gives the length of the box (B), which is the horizontal tube of the box. Then measure the length of the arm. He places it against the wall, gives him a pencil to hold it in his hand and orders him to hold it very long. This measure is multiplied by the coefficient 0,203 and the length (D) of the support comes out in the handle. Therefore, it has already adopted basic measures. With these measurements the geometry of the painting has been obtained.

But they also make more measurements. For example, the height of the chair, the distance from the leg to the ground multiplied by the coefficient 0.885, is simpler than that, put the bike on top and ensure that with the tips of the feet the floor is touched. The length of the vials can also be removed, approximately 20% of the distance from the crotch to the ground. The width of the knob can also be decided in advance and easily, only the width of the shoulder can be measured.

Custom bikes help you go more comfortably.

For more details, additional measures will be taken to prepare the bike flat or in slopes. For example, if you want a suitable bike to move better on the slopes — fast paced changes — the wheels that attach the frame to the rear fork will be shorter than normal and the angle of the chair will be lower than normal. If you need a harder or softer bike, more balanced or more difficult to handle, you will need to calculate and adjust the wheelbase, front fork tilt and steering angle.

The seller has taken half an hour to take all the measures and know the characteristics of the bicycle that the young man needs. If everything has been done well, the measurements will be sent to the workshop and soon will be made available to the bicycle. When you start walking, the boy may find the bike strange, because, despite its measurements, the body needs time to adapt. But the length, in addition to being more comfortable, will make the most of its characteristics.

Orbea, one of the great European bicycle builders, has an online service to buy custom bikes. To do this they use a special computer program in Orbea that designs the geometry of the bike frame depending on the morphology of the buyer and the bike you want.

The program performs a static and dynamic evaluation based on data. In the static evaluation it is analyzed if the position of the cyclist is the most suitable to get the most out of muscle work. The center of gravity position focuses mainly on the angle of the knees, the height of the shoulder and the position of the knees.

The dynamic evaluation, on the other hand, provides information about the strength that the cyclist exerts on the handlebar and the chair during the pedaling, that is, what part of his weight is placed on the handlebar and what part on the seat.

This technology is available to all those who want to buy a bicycle in Orbea, as bicycle vendors have the possibility to use this software in their stores. Measurements can be made in the store itself: They can access the Internet, join Orbea and use the program. This way the customer can suddenly have the characteristics of the bike he wants to buy.

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