Q&A

The right measure for a comfortable bike

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Parent Category: Q&A

Category: Q&A Biomechanic and Training

Published on Friday, 07 October 2011 07:49

Written by Luca Salvatelli

Dear Editor,

I want to buy a new bike and I am oriented on a Trek carbon (5.5) H2 geometry. Based on my following measures should like to know the best fit of the frame (56 or 58) the length and cranks, bearing in mind that I prefer a position in the saddle "highest".

height 181

horse measuring 86.5

bust measurement 59

arms measure 70

measuring the femur 48.5

measuring leg (bottom) 45

shoulder width 44

weight 70kg

Thank you in advance and I extend cordial greetings

Signed letter

Dear Reader,

it is difficult to answer truly comprehensive measures of a bike without a thorough analysis of the rider, with reference to the qualities and skeletal muscle of the subject. Two people can have the same measures, but completely different needs. Keep in mind that my assessment is therefore based only on a small base of data needed for a real assessment (although many centers are the only ones who need biomechanical ...). Considering all would opt for the size 56 and 175 mm cranks; this as opposed to a more correct size 58 and 172.5 cranks. With the size 56 will find a greater driving comfort and if it needs it will extend the attack to find a more aerodynamic position. This solution has a fault greater difficulty driving because of an imbalance in the distribution of weights. A solution adopted by many Pro to have a smaller frame, lighter and more reactive due to the stem longer. In essence you have a bike more "nervous". Everything if he wanted to extend his position, which I do not think the interest. For the crank a measure that will allow her to 175 mm have a greater thrust, therefore may use a slightly longer value, or alternatively, face an uphill with ease. On the other hand reduces the cadence of 3-4 rpm, but I find it irrelevant. Also stress the joints and ligaments of the knee, in the absence of pathologies in place, the more stress is completely irrelevant. Alternatively use the classical measure of 172.5, but note that the limit is, so it may be safely used by a crank 175.