Need replacement stem measurement help!
 

Hello all,
Pulling up to my apartment at the end of my Friday commute, my stem snapped. Now I need a new one, or I'll have to ride the train to work! Problem is, I'm a little confused re: measurements. Little help?

As I understand it, the following are the most regularly used measures of a stem:
Length
Angle
Clamp diameter
Steerer diameter

Here's what I've come up with so far, and my confusion.

Clamp diameter:
I measured the circumference of my Cinelli bars (3.25" = 82.55mm), and used this tool to find the diameter of the bars (26.276mm). Does this mean I'm looking for a 26.4mm clamp, as suggested by Sheldon?

Steerer diameter:
I measured the inside of my headset (am I right about this? see pic) and came up with 7/8". Does this mean that I'm looking for a 22.2mm or 25.4 mm stem?

http://lh6.ggpht.com/_qrci8fHZ1sI/Si...0/IMG_0325.JPG

In regards to the mechanical fit of the stem to fork and bars, what are the dimensions that I need to be searching for? Or, how do I go about figuring this out for myself? Point me to the threads I couldn't find?

Thanks!

You need a quill-type stem, 22.2 mm quill diameter.

if you are talking about vintage/old school Cinelli bars, you need a clamp diameter of 26.4 mm. The usual choices are 25.4 mm, 26.0 mm, 26.4 mm (pretty much Cinelli only), and 31.something (modern only).

The length of the quill, angle from the quill to the extension, and extension length (measured from center of quill to center of handlebar clamp) are also important. If you still have the old pieces, you should be able to jigsaw-puzzle them together enough to measure these dimensions.

Thanks much for the quick clarification and confirmation. Did I just miss out on an amazing eBay deal?

Just to clarify, when you say you're referring to what this pic calls Stem Angle and Extension, yes? And when you say that's like it's vertical extension?

http://www.habcycles.com/stemfit.jpg