Common cause of puncture welcomer — acting limit switches rim spokes. A protective ring belts rubber, mounted on rims of plants-izgotovitelej, a little stretchy, but over time, harden and break.
A reliable replacement could be the same ring from an old inner tube from the “Lada”. They are cut on either side of the large diameter of the camera — it turns out two great strips with a width of 17 mm.
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