I just picked these up and was wondering why the are like this, it came off a Ross bike, and that is all I know here are the pics.



First person with the answer get a hundred internetz.

I guess to adjust the wheelbase/trail.

Maybe to maintain brake clearance/performance for switching between 27in wheels and 700c wheels?
-Gene-

they are to keep the wheel from falling out if the quick release comes loose, for awhile, companies came up with all sorts of weird designs in fear of lawsuits

If it's obviously a low(er)-end bike, I'd say it's this, actually.
-Gene-

Is it "really" such a dumb idea ?

It's unclear in the photo if the slots provide a vertical or horizontal adjustment. I see what appears to be a subtle rake in the fork, indicating that the eyelets are on the back, as opposed to the top? Knowing which, would aid in determining the function.

I sold Ross bikes in the'70s which had these drop-outs. They were for keeping the wheel from falling out, just as the previous poster said.

^correct^ and they were not just on the lowest-end Ross bikes, but they were (thankfully) short-lived.

many higher end Schwinns of the era had some really irritating tabs screwed to the inside of the front forks

yeah, another USA innovation to comply with the CHP-mandated "safety rules"...wonder how many lives (or teeth) that actually saved? Lucky for us these innovations all morphed into the ubiquitous "lawyer's nubs" that we can grind off in a couple minutes

I've always removed the Schwinn tabs when I encounter them but I'm re-thinking that. I bought a couple of nice Italian bikes from a guy who gave up cycling after losing his front wheel while trying to jump a curb. Needless to say it was a terrible accident and the effects will be with him the rest of his life.

I find the lawyer tabs annoying but the consequences of a single goof can be life changing. Just sayin'