Originally Posted by
Ronno6
Upgrading to 7 speed will most probably require a new chain and possibly
crankset in addition to the gearing changes.
I am not sure if the wider chainring spacing of a 5 speed crankset will have shifting problems
with the narrower 7 speed chain.
No, most all recent chains are 6/7 speed compatible, so the chain likely will work OK with a narrower freewheel, and there will be no problem with the chainwheels.