I think you should change the quads, hamstring, and calves to Monday. Legs requires a lot of energy and effort to train properly. Two days of rest will ensure your body has sufficient reserves for the demands for training the legs.
Training the biceps before the day you train the back is backwards. Your back training will require rested biceps for the rows and pulldowns for training the back.
My split routine is also four days;
Monday - quads, hamstrings
Tuesdays – chest, shoulders, triceps
Wednesday - rest
Thursday – back, traps, biceps
Friday – abs, calves
Saturday – rest
Sunday – rest
My split routine is a basic push-pull routine. I train the pushing muscles on the same day,Tuesday, and the pulling muscles,Thursday, on the same day.
The legs are trained on a separate day, the first training day of the week. The abs and calves are trained on the last training day of the week.