MORGANTOWN, W. Va. – The 2014 AMSOIL Grand National Cross Country Series presented by Maxxis makes a stop in Union, S.C. this weekend, April 12 and 13, for Round 4 of the 13-race AMA National Championship series. While the first three rounds have been unpredictable in terms of weather and results, the one constant has been the tightly contested championship battle between Factory FMF/KTM’s Charlie Mullins and Kailub Russell.