Tandem Cycling - Stem Question

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View Full Version : Stem Question


bschoen
12-07-06, 10:07 AM
Hello All!

Just recently picked up the new tandem - just in time for winter - wouldn't you know. My wife likely won't get on it with me till Spring!!!!!!!!! Anyway......

In trying to replicate (as much as is possible) my single bike setup, it has become apparent that the reach of this bike is a bit longer and lower than I prefer. Having some disc issues with my neck it is important that I ride slightly more upright. Witness the Specialized Sequoia Elite which serves as my single.

I believe my best approach is to adjust these two dimensions (reach and rise) by changing out stems. The bike is set up with a Ritchey Pro stem now, and for esthetic reasons I'd like to stay with Ritchey. I hit their website and am a bit confused. The stem currently on the tandem (Inga - by the way) is at least 110 and I'll likely need to go with a 100 or 90 - that's yet to be determined. But once I settle on the saddle position, I'll have no difficulty determining which length. My question has to do with the "rise" part of the equation.

I see Ritchey's stems listed with "Angle 84/73". I presumed this refered to the degrees offset from vertical. For example: the 84 stem would have a "rise" of 6 degrees above horizontal. However, Ritchey also has a "Pro 30 degree" stem which also lists "Angle 84/73" in the specs.

Can someone explain how "rise" is measured and how to reconcile the Pro 30 degree stem with the fact that its listed with an angle of 84/73?

Thanks bunches.


jnbrown
12-07-06, 02:59 PM
I have a Ritchey stem on my road bike. It is 73 which means you get +/- 17 degress depending on which side you mount it. Generally Ritchey makes either 73 or 84 degree stems. 73/84 may indicate that a certain stem comes in 73 OR 84. With 84 you will get +/- 6 degrees of rise. Ritchey and others also make an adjustable stem which you may find helpful.

Hope this helps - Joel

dfcas
12-08-06, 12:43 PM
http://www.habcycles.com/fitting.html


Steve Katzman
12-08-06, 01:32 PM
I'm betting it's a mistake on the website.

The Ritchey Comp 30 does not have the conflicting data that is apparently on the Pro 30. My guess is that some webmaster cut and pasted the description from another stem and forgot to edit out the part which gave the choice of angles.

As far as explaining rise, the chart that dfcas links to is pretty self explanatory. Keep in mind that the stem angle in degrees is not measured from horizontal. They are measured from the normal (right angle) to the steerer tube which is already angled up around 16 to 18 degrees, depending on the head tube of the frame in question. So even a stem with 0 degees of rise (90 degee) will still bring the bars up. This is covered (somewhat cryptically) in the note on the Habanero stem chart.

Enjoy your new tandem.