There are 2 drain plugs underneath the VTX 1300 you need to remove both of them plus the oil filter if you have changed the filter and drained both plugs you should add 3.9 quarts of 10-30 or 10-40 oil. Be careful about the type of oil you buy make sure the oil says compatible with wet clutch. I run Amsoil synthetic it has really long change intervals and is supposed to be the best out there. The drain pugs are 17mm hex plugs or 11/16 will work.