This paper presents the result of experimental study on traction forces, traction efficiency generated by the different tyres in different soil conditions. The field experiment was carried out in forest conditions. The relationship between type of tyre (there was used four type), values of vertical load (there were used five level of loading), traction forces and the level of traction efficiency are studied. In experiments double tyre and with tyre chain was also carried out with. Experiments showed that using double tyre and tyre chain are good way to improve traction properties, and that each tyre has optimal vertical loading for the best traction properties.

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