I rode up to thunder bay last year via 17(across the top of lake huron then around the east and north of superior)
I solo'd it,I would not do a ride like that again alone,I found I was just too bored in the evenings,but the weather was **** most of the time too so it kept me indoors a lot.What ever you do don't stop in blind river on 17 ,that town is a **** hole.Their are a lot of bears north of sue saint marie that like to wonder onto the road(i've heard about the moose too but i didn't see one)also the opp are everywhere north of the soo.I was told by a local in wawa that's where they train new opp recruits.The best riding was north of a town called marathon and the scenery is the best ontario has to offer in my opinion.Meh I'd probably do it again and just hope for better weather.I've never been passed thunder bay so i don't know about manitoba,saskatchewan,but I think the posters above are probably right on the money when they say flat and boring.I wouldn't worry about gas ,their are gas stations a plenty,I think the longest stretch between stations for me was about 175 kms.I met some really cool people when i stopped for food/gas,country folk seem to be much more friendly than city people
edit-threw up a couple pics-just give er man lol i doubt you'll regeret it !
To avoid taking the 400 all the way up to sudbury,I would ride to robermory and take the ferry across to manitoulin,it's nice to chill on the ferry for a couple hours,manitoulin island is georgeous and east manitoulin has some decent twisties also....ahhh now i'm jonesing to do a long ride again,hope it warms up soon......