Length of chain determines wheel base.Not size of sprockets.
I run 13-49.There are areas that you have to ride it a little harder carrying speed in tighter stuff.But the wider gaps for climbing big hills without shifting and the warp over drive feature when you need it is well worth the trade off.
Having the chain more in line with the bottom profile of the rear sprocket and keeping the chain running through the rear chain guide instead of dragging across it is also a big factor.
I run 13-49.There are areas that you have to ride it a little harder carrying speed in tighter stuff.But the wider gaps for climbing big hills without shifting and the warp over drive feature when you need it is well worth the trade off.
Having the chain more in line with the bottom profile of the rear sprocket and keeping the chain running through the rear chain guide instead of dragging across it is also a big factor.