TheSourMilk

Simply looking for any recommendations folks may have on roads between these 2 points that have more of a shoulder than the common Connecticut back road.

For anyone curious Im planning the second day of a 2 day adventure from the greater Portland, Maine area to my old home town outside of Hartford, CT.

Thank you.

bktourer1

Rts. 9 & 20 Westbound have several places where the shoulders are wide for a bike.
Get the Rubels bike maps for Mass. Some maybe out of print.
From Springfield there is the Farmington River Trail which you can pickup in places, Some sections are works in progress,

UniChris

Westfield, not Springfield, also more the canal line trail than the Farmington River trail (if anything that refers to the Farmington Collinsville branch) . Additional problem for the asker is then you end up on the wrong side of a ridgeline from Hartford, though I've toyed with the idea of trying to get through. The river ultimately does.

And getting from Boston to Westfield or even Springfield doesn't have great options.

For the original question I'd at least research the ECG routing between Boston and Hartford as something to compare to other possibilities.