John W. from Pittsburgh, PA on 5/8/2017 11:12:26 PM:
September might be the best month to travel! Days will still be summery and warm but not the brutal heat of Mid-summer. Daylight will be a bit shorter but doing a six day schedule you will be making town comfortably before dinner time.
My bike was a Trek 7.3 D.C. With 32 mm tires. You be totally fine on the GAP and in pretty decent shape on the C&O, just a few puddles if it has rained. September should be too rainy but you really can't predict.
My 5 day trip was Ohiopyle, Cumberland, Hancock, Harpers Ferry, DC. If stretching it to 6, get rid of Ohiopyle (which was 78 miles on first day) and replace with Connellsville and Rockwood, then into Cumberland.
Don't forget the Western Maryland Rail Trail on each side of Hancock. 22 miles of paved asphalt that runs parallel to the C&O. Good luck!