Another 110W125 question... gears.

[rlevine]

I just received a Singer 110W125 head, and started in on some cleanup. Given everything I've read here and all the documentation I've found, I expected it to be geared for very small stitches, and I'd need to replace gears to get to stitch lengths at the large end of its range, say 12/16/18-ish spi. 

I was very surprised to find that the gears in the machine are feeding at 9, 9.5 and 10 spi. They're also not the gear numbers from the 1930's-vintage 110W parts lists I have, but match the gears sets from 136W post machines. 

I pulled the needle and tried measuring again, wondering if the needle rocker was interfering with the stitch length , but it's consistent. 

Any thoughts on the peculiar gearing and why I'm getting something that I thought the machine couldn't do? (Or if there's an obvious mistake I'm making, of the "of course the stitches are long, you're forgetting to set the <blank> before measuring") variety.

Thanks!

Rick