What is this? Weird frame nub content...
 

So I just finished fixing up a 92 (I think) Giant Yukon. Nothing real top of the line, but a solid bike, and will make a great commuter for someone.

http://img.photobucket.com/albums/v1...DSC_0738-1.jpg

And I noticed this weird braze-on/nub on the non drive side chain stay. Never seen one before and can't even imagine what it might be for. Any ideas? I thought it might be something to do with the quick release lever, but the lever doesn't even touch it.

http://img.photobucket.com/albums/v1...DSC_0747-1.jpg

That is weird. When you figure it out be sure to let us know.

might be a fixture for a proprietary rack, or maybe a fancy mounting point for the brake arm of a coaster brake hub... IDK.

I'm stumped, but very curious. Clean up the rust on that QR before you try to sell it!

I have the identical bike, never notice that.

I'm guessing an anti-rotational nub for a rear kick stand, but that's a guess.

I agree with that conjecture.

Would make sense with the two bolt holes in that dropout.

I'm guessing a mounting and anti rotational nub for a disc brake system.

I think that bike is too old for a brazeon for a disc brake. I lik the Kickstand idea or maybe something for a kid trailer?

Was the frame assembled in a automated welder? Might be for indexing purposes.