The tire includes a summit surrounded by side portions terminating in beads provided to cooperate with a mounting rim. A carcass reinforcement is surmounted by a summit reinforcement composed of reinforcing plies. When the tire is mounted onto its standard mounting rim and inflated with its nominal pressure, each side portion has an upper side point, a bottom side point, an intermediate side point, an upper side portion, and a bottom side portion. A weight of the bottom side portion on one side portion is at least 15% lighter than a weight of the bottom side portion on another side portion.