To provide a pneumatic tire capable of preventing the tire from coming off a rim without worsening the assemblability of the rim and riding comfortableness even when a second bead core is buried into a rim protect bar.
In this pneumatic tire, the rim protect bar 4 having an outer end part R protruding obliquely and outward in the direction of inside diameter of the tire toward an outer side in the direction of width of the tire is provided by corresponding to an outer end in the radial direction of a rim flange 21 of the rim mounted in an outer side region in the radial direction of the tire of a bead part 3, and the second bead core 10 is buried into the outer end part R to assemble on the standard rim 20 by pneumatic pressure of 200 kPa. When the load being 80% of the maximum load capacity is applied, a distance d1 at which the maximum inside diameter of an inner peripheral face of the rim protect bar 4 is apart from the outer end R in the radial direction of the rim flange 21 is 10-20 mm, and a distance d2between the maximum inside diameter and the minimum inside diameter of the outer end part R is 5-10 mm. When pneumatic pressure is 100 kPa, the maximum inside diameter of the inner peripheral face of the rim protect bar 4 is abutted on the outer end in the radial direction of the rim flange 21.
Takashi Noguchi
Kazuhiko Saishita