I want to tweak the fit of my '83 Trek 730 slightly by replacing the original stem with one that's shorter in the horizontal dimension, to bring the bars a little closer to the seat. I want a stem that looks similar to what I have now, just for aesthetics. I'm pretty sure it's a 1" quill. I measured the thickness of the bars at the center at 25.4mm. The horizontal length of my existing stem seems to be about 110mm (center to center). On eBay I see some Origin 8 stems that seem right, but there's one dimension I don't understand. Can someone tell me what part of the stem has a dimension of 22.2mm?

Copied from eBay description:
# FORGED ALLOY POLISHED
# 60MM CENTER TO CENTER
# -17 DEGREE ANGLE
# 22.2 x 180MM LENGTH QUILL
# 25.4MM CLAMP
# 1" QUILL

Thanks,
Dan

22.2mm = inside diameter of the steerer tube our outside diameter of the stem shaft. That's the standard size and should fit your Trek (many French bikes take a slightly smaller--22.0mm--stem). I'm not sure how Origin8 measures height (the 180mm dimension), but it's likely from the minimum insertion line to the top.

Neal

Thanks Neil. That answers my question enough to go ahead and make the purchase. Now, just to satisfy my curiosity, to what does the 1" dimension refer? I had assumed that was the inside diameter of the steerer tube but now I know better. Maybe it's the outside dimension?
Thanks,
Dan

The 1" is the OD of the steerer.