Bike pedals used to put a metal screw cap to protect the bearings from contamination. Now, instead, use the plastic plugs, which are often lost. Rescue plastic or nylon tubes from medical bubbles. Such substitutes being kept quite steady.
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BIKE “ON THE CONTRARY”? The VELOMOBILE!
In the journal "modelist-Konstruktor" No. 4'2003 was a good publication about the interesting developments of the members of the club of Tambov veloturistov: different models for every...
ACCORDING TO THE PRINCIPLE OF COMMUNICATING VESSELS
...it is possible to make a device for determining the marks in the construction of garden buildings. For this you will need a long hose with transparent bits filled with water.
