I was asked by one of the moderators to take a look at this bike and give my opinion. My process it always to start with the frame and work my way out. I looked through my references for an identical match and was unable to find one but several details lead me to believe the frame can be attributed to Manton and Smith. M&S was one of the smallest volume American bicycle manufacturers; they were headquartered in Chicago and they produced bicycles between the mid 1930’s and the mid 1950’s. Unfortunately, very little is known or is easy to find out about their production and models that do turn up feature many design differences that suggest ongoing design changes over the full history of the company.
The hallmark of their frames is the hand welded tube joinery and that those welded beads look very much like modern TIG welds. That is the primary reason to attribute this frame to M&S, in addition the dogleg of the seat stays, the somewhat abrupt transitions in the curvature of the down tube, and the form of the rear dropouts are all features that show up in the M&S pattern book.
M&S bikes are often confused with Schwinn products, first because of similar geometries and secondly because the tube joins are external welded fillets. The joints do look generally similar but Schwinn frames employed the use of brazed filleted joints (before electro-forging) that were cleaned and rounded after being welded unlike the joints on M&S bikes that are physically smaller and left natural. Another area of confusion is that due to their small size, M&S relied more out outside suppliers for many of the parts that completed their bikes and some of those parts are similar or identical to parts supplied to the larger manufacturers leading to miss-identification.
Moving beyond the frame I believe the bike as it currently stands has to some degree been reconstituted aftermarket. The fork appears to be a 1936 Schwinn locking fork with the centered, non-angled key position. The frame is definitely newer than 1936 as is witnessed by the general form of its geometry. If the bike is indeed an M&S product the fork lock is doubly curious because the one feature M&S was best known for was their proprietary in-head Bike-Loc system for accomplishing the same result. Still, not all M&S frames had the Bike-Lok feature and this fork may have been added to the frame when it was refurbished.
The last point to comment on is that the decal, and the pin striping are the product of a refurbishment by an owner and that is also likely the source of the Coppertone finish on the frame and fork which as a color is more modern that the underlying frame.
As I noted at the start of this post, you are getting my opinion on the bike rather than a definitive response based on my finding an exact duplicate of this bike or a direct literature reference. It seems to split differences between several frames I did study for this answer with nothing coming up to dissuade me from posting. From what I could find it is also hard to place all of the features of this frame in a definite location along an M&S timeline. I would hazard that it is a late prewar or early postwar frame as the rear exit toe plates were changed to front dropouts in the late forties.
