Abstract: In a tire 2, an outer surface 52 of a crown rib 48e and an outer surface 54 of a shoulder rib 48s form a part of a tread surface 28. On a cross-section of the tire 2 along a plane that includes a rotation axis of the tire 2, an outline of the outer surface 52 of the crown rib 48e is represented as a first arc. A center of a circle to which the first arc belongs is disposed on the equator plane. An outline of the outer surface 54 of the shoulder rib 48s is represented as a second arc. A ratio of a distance from a center of a chord of the second arc to the second arc relative to a length of the chord of the second arc is not less than 0.03 and not greater than 0.05.

Abstract: A pneumatic tire includes a tread portion provided with a pair of central blocks arranged on both sides of a tire equator. Each of the central blocks includes a ground contacting face having an axially inner block edge facing the tire equator. The inner block edge extends in a V-shaped manner including a first inclined edge and a second inclined edge inclined in an opposite direction to the first inclined edge. The second inclined edge has a circumferential length shorter than a circumferential length of the first inclined edge. Each of the central blocks includes a first portion having the first inclined edge and a second portion having the second inclined edge. The second portion of the central block includes an end wall at an opposite side to the first portion. The end wall includes a stepwise wall extending in steps toward a groove bottom.

Abstract: In a tire 2, an outer surface 52 of a crown rib 48e and an outer surface 54 of a shoulder rib 48s form a part of a tread surface 28. On a cross-section of the tire 2 along a plane that includes a rotation axis of the tire 2, an outline of the outer surface 52 of the crown rib 48e is represented as a first arc. A center of a circle to which the first arc belongs is disposed on the equator plane. An outline of the outer surface 54 of the shoulder rib 48s is represented as a second arc. A ratio of a distance from a center of a chord of the second arc to the second arc relative to a length of the chord of the second arc is not less than 0.03 and not greater than 0.05.

Abstract: A pneumatic tire comprises shoulder land zones and middle land zones divided by shoulder main grooves and a crown main groove. The shoulder land zone is divided by shoulder lateral grooves into shoulder blocks. The middle land zone is formed as a circumferential rib in substance. The middle land zone is provided with first and second middle outward slots which extend from the shoulder main groove toward the axially inside beyond the widthwise center line of the middle land zone, while gradually decreasing the width and inclining with respect to the tire axial direction at an angle ?1 and an angle ?2 (?2>?1), respectively, and terminate within the middle land zone. The open ends of the first and second middle outward slots respectively face the open ends of the shoulder lateral grooves at the shoulder main groove.

Abstract: A pneumatic tire includes a tread portion provided with a pair of central blocks arranged on both sides of a tire equator. Each of the central blocks includes a ground contacting face having an axially inner block edge facing the tire equator. The inner block edge extends in a V-shaped manner including a first inclined edge and a second inclined edge inclined in an opposite direction to the first inclined edge. The second inclined edge has a circumferential length shorter than a circumferential length of the first inclined edge. Each of the central blocks includes a first portion having the first inclined edge and a second portion having the second inclined edge. The second portion of the central block includes an end wall at an opposite side to the first portion. The end wall includes a stepwise wall extending in steps toward a groove bottom.

Abstract: A pneumatic tire comprises shoulder land zones and middle land zones divided by shoulder main grooves and a crown main groove. The shoulder land zone is divided by shoulder lateral grooves into shoulder blocks. The middle land zone is formed as a circumferential rib in substance. The middle land zone is provided with first and second middle outward slots which extend from the shoulder main groove toward the axially inside beyond the widthwise center line of the middle land zone, while gradually decreasing the width and inclining with respect to the tire axial direction at an angle ?1 and an angle ?2 (?2>?1), respectively, and terminate within the middle land zone. The open ends of the first and second middle outward slots respectively face the open ends of the shoulder lateral grooves at the shoulder main groove.