All about bicycles, electric-assisted bikes, technology and safety in the press

In our daily work as we deal with bicycle safety, technology and user manuals we come across lots of safety risks. The most frequent ones are published in articles of the leading German special-interest magazines TOUR – Europas Rennrad-Magazin Nr. 1, BIKE – Das Mountainbike Magazin Europas Nr. 1 and E-Bike – Das Pedelec-Magazin to make this information important for the sector accessible to a wider public.

For many years now the Eurobike Show Daily accompanying the annual international Eurobike Show has given us the opportunity to publish our perspective on major developments in the cycle industry in full-page articles.

We also speak regularly in independent lectures about all topics relating to bicycle technology and bicycle market. In addition, we are regularly cited by further special-interest magazines or trade journals as well as more and more by radio and television and in their media reports, which shows us that we are completely right with our information. The section NEWS informs you about the latest news from our specialist fields. The reports and publications of this section are listed chronologically or according to topics of interest.

TOUR 06/2011
Reading time 1:20 minutes

Never without torque wrench

Seat post assembly - never without torque wrench

TOUR: Are seat posts particularly prone to defects?
ZEDLER: Broken seat posts are among the most common damage on bicycles with partly serious consequences for the rider’s life and limb. The single-bolt patent clamping of lots of often simple seat posts is far on top of our loss statistics. This type requires extremely high and precise torque settings which must be observed strictly and which can’t be achieved with a minitool or an Allen key. The dual function as adjusting device and single hold of the saddle is what all too often brakes these bolts literally the neck.

Are there any principal differences between aluminium and carbon seat posts?
High value aluminium seat posts with double bolt clamping often do not cause any problems. In the case of carbon seat posts the problems have shifted from the seat post head to the clamp of the seat post in the frame. To achieve a reliable hold, it is often the case that clamping forces are used which crush the sensitive to pressure carbon tube and lead to an initial damage. If additional stress occurs, in particular due to tough road impacts, pre-damaged carbon seat posts can fail.

How can you prevent a seat post breakage?
The mounting is of major importance. The seat post diameter must precisely match the seat tube. The seat tube must slide into the seat tube without play. It is necessary to apply carbon assembly paste on the clamping surface to increase the friction and to be able to reduce the torque values of the bolts.

What to do when no torque wrench is at hand?
Even with a minitool you can pre-damage a seat post. Therefore, it is inevitable to use a torque wrench for mounting. By the time it will also give you a feeling for torque values, it is a good master. Once you have understood that, you are even able to readjust a carbon seat post on your way.

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