S.C. Code Ann. § 56-5-3430: Riding on roadways and bicycle paths.

(A) Except as provided in subsection (B), every bicyclist operating a bicycle upon a roadway shall ride as near to the right side of the roadway as practicable. A bicyclist may, but is not required to, ride on the shoulder of the roadway in order to comply with the requirements of this subsection.

(B) A bicyclist may ride in a lane other than the right-hand lane if only one lane is available that permits the bicyclist to continue on his intended route.

(C) When operating a bicycle upon a roadway, a bicyclist must exercise due care when passing a standing vehicle or one proceeding in the same direction.

(D) Bicyclists riding bicycles upon a roadway shall not ride more than two abreast except on paths or parts of roadways set aside for the exclusive use of bicycles.