Why 3 Holes in the Chain Ring?

[Road Master]

I've never seen a chain ring with 3 holes in it before - what's up with that? Going by the wear mark on the sprocket it's my guess these two parts didn't go together originally because this crank doesn't cover the wear mark. Looks like the crank says CA2-10 on it. Don't know what that means if anything. And this sprocket is real rough cut. No round or smooth edges - everything is sharp. I'm still trying to learn about this stuff so any info is greatly appreciated. Thanks.

 

[Rustinkerer]

I think it was just part of the design. That's most commonly seen on Shelbys, but it goes back to the teens I believe. It likely would have had a dog leg offset crank. ~Adam

 

[Chainsaw]

Cosmetic reasons most likely. Them old sprockets were artwork.

 

[stretch]

ditto. they took pride in everything, and a sprocket was designed to be symmetrical, no matter what. so the extra holes are to prevent it from looking funny.

 

[deorman]

It's been a while since I looked real close at a really old crankset, but I don't think they had those dang slotted washers. :? More likely a full cover dust cap that interlocked with the inner race. The crank arm itself looks pretty old, but kind of narrow, maybe from a early middle weight?

 

[B607]

I've got a picture in a book around here somewhere that shows a 1911 Hawthorne with that same ring. Gary