A streamlined tailfin pivotably attached to a shaft-shaped member disposed on a vehicle provides for reduced drag in winds varying in direction impinging thereon.

A tire has a block pattern. The block pattern includes a plurality of linked block pairs. Each linked block pair includes two blocks 28 and a tie bar 30 interposed between the two blocks 28 and linking the two blocks 28 together. The tie bar 30 has a toe end 40 having a height equal to or smaller than a height of the blocks 28 and a heel end 38 having a height smaller than the height of the toe end 40.

A tire includes a block 30. The block 30 includes a land 36b, a transverse groove 48b, a longitudinal groove 50b, and a side surface 38b. The land 36b is flat. The transverse groove 48b is recessed from the land 36b. The transverse groove 48b has inner and outer ends 52 and 54 in an axial direction of the tire. The inner end 52 of the transverse groove 48b is open on the side surface 38b. The outer end 54 of the transverse groove 48b is not open on the side surface 38b. The transverse groove 48b is localized in the inner region of the block 30 in the axial direction.

A pneumatic tire assembly includes: a tread portion including one or more traction features; a first sidewall portion coupled to the tread portion; and a first bead portion coupled to the first sidewall portion; wherein the first sidewall portion includes multiangle first tread traction features positioned proximate the tread portion.

Provided is a tire for a motorcycle for uneven ground traveling capable of continuously exhibiting good grip performance. The tire for a motorcycle for uneven ground traveling includes a tread part on which plural crown blocks are formed, and at least one of the crown block has a wheel tread, a first side surface, a first edge arranged between the wheel tread and the first side surface, a concave part that opens on the wheel tread and the first side surface, and a second edge arranged between the wheel tread and the concave part. The wheel tread has at least one external corner part in which an angle between the first edge and the second edge is an acute angle.

A motorcycle tyre for traveling on rough terrain, the tyre includes a tread portion provided with blocks. The at least one of the blocks includes a ground contact surface having a pair of lateral edges extending in a tyre axial direction. The at least one of the blocks is provided with a pair of lateral narrow grooves extending in the tyre axial direction on the ground contact surface to form a pair of edge-side portions defined between the pair of lateral narrow grooves and the pair of lateral edges. The at least one of the pair of edge-side portions includes a neck portion having a minimum circumferential length thereof, wherein a circumferential length of the at least one of the pair of edge-side portions increases toward axially both sides from the neck portion.

A pneumatic tyre includes a tread portion, and a pair of buttress portions each extending inwardly in a tyre radial direction from a respective one of tread edges. At least one of the pair of buttress portions is provided with side protectors protruding outwardly in a tyre axial direction. The side protectors include first protectors arranged in a tyre circumferential direction. Each first protector includes a lateral V-shaped portion including a first inclined element inclined with respect to the tyre circumferential direction and a second inclined element inclined in an opposite direction to the first inclined element with respect to the tyre circumferential direction and connected to the first inclined element.

An aerodynamically optimized drag-reduction means and method for optimal minimization of the drag-induced resistive forces upon a terrestrial vehicle wheel, where the drag-induced resistive moments on wheel surfaces pivoting about the point of ground contact are reduced, and the vehicle propulsive forces needed to countervail the resistive forces on the wheel are reduced. The drag reduction means includes: a streamlined wheel cover positioned on a vehicle to shield the faster moving upper wheel surfaces from headwinds; a streamlined wind-deflecting fairing positioned on a vehicle to shield the faster moving upper wheel surfaces from headwinds; an engine exhaust pipe disposed on a vehicle whereby exhaust gases deflect headwinds to shield the faster moving upper wheel surfaces of an automotive wheel; an automotive spoked wheel having streamlined oval-shaped wheel spokes arranged in one or more rows for greater axial strength; a streamlined tailfin rotatably attached to a wheel spoke, which thereby may pivot about the spoke in response to varying crosswinds; and a tire having streamlined tread blocks arranged in an aerodynamic pattern.

A tire includes a tread portion. The tread portion is provided with grooves each having a pair of groove walls. At least one of the groove walls is provided on a surface thereof with a pattern portion having a plurality of micro-protrusions. The pattern portion is provided with the micro-protrusions at a density of 1 to 5 per 1 mm.sup.2 of the groove wall area.

The tire has first crown blocks each including a ground contacting surface and a block wall surface. The block wall surface includes a first block wall surface adjacent to crown grooves and a second block wall surface adjacent to a first shoulder circumferential groove. The first block wall surface is provided with a chamfered portion on the ground contacting surface side in a range of 50% or more of a length of the first block wall surface. The second block wall surface is either not provided with the chamfered portion or provided with the chamfered portion in a range of less than 50% of a length of the second block wall surface.