The edge part of a bobsled is a location where external forces are repeatedly applied in the bolt axis direction and perpendicular to the axis due to vibrations, leading to loosening and potential breakage of bolts. By changing the edge fixing to a hard lock nut, it has become possible to tighten at any position and to eliminate the loosening problem while providing a certain amount of play to absorb impacts.

• Areas where the bobsled is constantly subjected to impact loads as it slides at high speeds on ice, making it prone to bolt and nut loosening.
• Areas, where play is necessary for the fastening part to absorb irregularities on the ice, and tightening too strongly, is not possible.

• It has become possible to tighten at any position.
• The loosening problem has been solved.