Joined: Feb 2012
Posts: 19,344
Likes: 5,462
From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Rarely is it worthwhile to add cost to a defective product to then sell it at a discount.
These look to be typical reinforcing gussets or triangulations. Attempts to more the bending moment further out from the joint.
Some will say these indicate a "burly" frame, others say that a well designed and built frame shouldn't need extra gusetting. Andy.