The wife & I just spent the past couple of days over near Holland & like most of Michigan's hwys, I-196/US31 was under construction for a couple of miles(around the 25-30m.m. IIRC).
Although Google maps says the routes north from S.B. to Frankfort are only 20 minutes & 20 miles different, I'd take the US31 route vs. the US31/196/US131/M115 route.
US31 thru the Holland area north to Grand Haven will impede rapid travel a bit as it's a local divided hwy mixed w/ stop lights, but riding US31 north & taking M22 north from Manistee is more enjoyable(besides, M22 has the views, especially the Arcadia Bluffs about 5 miles north of Arcadia(
http://www.waymarking.com/waymarks/WM2502_Arcadias_North_Bluff_The_Sunset_Over_Look ), IMO, than slabbing it to US131 north from Grand Rapids & splitting off on M115 at Cadillac & heading into Frankfort from there. However, there are passing lanes on M115, but the occasionally numerous local/sheriff/state patrols along that route are detrimental to heavy throttle hands, not to mention the forest rats that are lurking about
If you've got enough time, continue to follow M22 north from Frankfort around the little finger into Traverse City, connecting w/ US31 north again into Petosky & another of the few jewels of Michigan
M119(watch for the secluded driveways & sand on the road). Be sure to make a stop at Leggs Inn in Cross Village & enjoy a beverage & or meal overlooking the big lake from their patio.
http://www.legsinn.com/ From Cross Village, continue north along LakeShore Dr. to Lakeview Rd. east(changes to Gill Rd.) & back to US31 again. Heading north brings you to Mackinaw City & the
BRIDGE. Once across, & if you're heading west along US2, make a stop at Gustafson's for some of the best smoked fish & beef jerky here in the states!
http://www.roadfood.com/Restaurant/Reviews/300/gustafsons-smoked-fish-and-beef-jerky That's all I can recommend, as it's been 12 yrs. since I've been west of there.