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...AFAIK, the majority of the Falcon frames with that seat stay treatment were straight gauge Reynolds. ( I hesitate to say all any more.) It showed up on a lot of different models over the years, and they typically had stamped dropouts. Black Diamond was one, but there were a lot of different names. They even had some deal with Merckx for a while, where the same frames were used on models painted orange. I like the way mine rides, which is why I powder coated it.

It's worth building up to see if you like the road feel of it. Then, I guess you could repaint it if you wanted to.

The top end Falcon bikes from those years used forged dropouts and a different seat stay attachment. They also had more chrome (lugs, stay ends, etc.)