How are the new threadless stems measured?
Hello all, First time on this neat site so bear with me.
I am presently rebuilding my old Columbus steel frame (from the 80's) and am seeking knowledge on the new threadless stems. My old Cinelli quill stem (at my best measurement) is 12 cm. I'm looking at either a new 12 cm or 13 cm Ritchey Pro, because of price, quality and my body make-up.
My question is: HOW ARE THE LENGTHS DETERMINED??? Meaning is the length measured from the center of the holes or from the outside edge???
They are measured the same way as the old, quill stems; from the intersection of the steering column axis and extension axis, to the intersection of the extension axis and handlebar axis. In other words, along the central axis of the stem, from the centre of the fork hole, to the centre of the handlebar hole.
You do realize that you will require a new headset and fork to use with this stem, unless you get a quill adapter? Also that threadless stems are sold with different amounts of rise, and that you need one with -17 degrees of rise to have a stem extension that is parallel to the ground, like a standard, road, quill stem?
Thanks for the answer, that's what I thought it was. Also in response to your answer, I'm pretty well re-doing the whole bike from the ground up. It's my winter project. I live in Canada and have been pricing gruppos and gear all across North America. If anyone else is reading this ... feel free to advise of any decent shops/businesses you have dealt with that will $hip to Canada.
The "rise" info is interesting as I thought the +/- 84/6 degree stem was the style that "levelled" your stem/handlebar set up. I was good in english ... no sorry that was gym class.
Thanks for the feedback. For a "newbie" I'm pretty impressed with this forum.
Originally Posted by T-Mar