Abstract: The invention contemplates an improved traction-drive transmission of the variety in which plural planet wheels are radially displaceable in orbital motion about an axially opposed pair of axially shiftable sun wheels and within an axially opposed pair of rotationally fixed reaction rings, said planet wheels having constant angular-contact with the wheels and rings of both pairs. An axially fixed pivotal reference between the sun wheels is used for linked connection of the sun wheels such that displacement of the respective sun wheels is always equal in magnitude but in opposite axial directions with respect to the axially fixed reference, thus assuring that the instantaneous radius of planet-wheel orbit between the sun wheel and reaction ring on one axial side of the fixed reference will at all times match the instantaneous radius of planet-wheel orbit between the sun wheel and reaction ring on the other axial side of the fixed reference.