If you are seriously intending to ride only Rt.20 all the way, I might suggest a bypass when you get to Rockford, IL. I would not suggest you take Rt.20 all the way through Chicago and its suburbs. Terrible traffic, stop light after stop light, and as you start heading south from downtown Chicago you will pass through some areas where much care would need to be taken. Rt. 20 crosses I90 at Rockford. Jump on I90 and take it east to South Bend, IN, visit the University of Notre Dame, and pick up Rt.20 again headed east. Or, stay on I90 all the way to Toledo and then pick up I90 again. I live in the NW suburbs of Chicago, Lake in the Hills, and I am about 9 miles from Rt.20, just south & east of where Rt.20 goes through Marengo, IL. If I can be of any help when you come through the area, PM me and I'll give you my phone #. Have a great trip, and a safe ride.