This paper presents the result of research on traction properties generated by different types of tyres on forest roads. There was different trees species and surfaces of the road: hardened by gravel and crushed stone. Research showed that the highest traction force was generated by the tyre 5.00-10 on crushed stone surface (604 N). Among grass type of tyres the highest traction forces were achieved for 18×9.5-8 on the same type of road (563 N). The most effective way to improve the traction force was to increase vertical load of the tyres. Highest values of the coefficient of adhesion were enumerated for drive wheel than it was for grass type tyres. Values of this parameter were depended on the road type. The experiment showed that using modifications sampled wheels achieved much highest traction force and coefficient of adhesion. The highest traction efficiency has modifieded carriage able on the gravel hardened road. For the tyre 5.00-10 traction efficiency was 82% and for 18×9.5-8 was 75%.

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