Those side fender stays are very stiff. So much so that if pushed in either direction,left or right, they will load the frame,and push it in that direction. You can imagine the fender centered between those misaligned stays. It's stored energy, constantly pushing my frame, from the left rear ,clockwise. So while your riding your bike, there's a push to the right, constantly. You don't feel the push, you feel the instability of you trying to keep the bars straight, while on the other side of the pivot, (steering head), the frame is pushing right. In this case I believe it is due to the fender stay mount, where it welded to the frame, not being welded in at the correct angle. Look closely at the pics. Notice the difference between the left and right welded in mounts? The difference is slight at that point, but at the other end of the fender stay its huge. See what I mean?
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