Is there anyway to know how much height or lift I will get from flipping a 12 degree 100m stem?
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Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
JimMoss wrote:
Is there anyway to know how much height or lift I will get from flipping a 12 degree 100m stem?Yes. It's called trigonometry :-)
http://bikeblather.blogspot.com/
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
http://yojimg.net/bike/web_tools/stem.php
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
http://www.ttbikefit.com/stemcalc.html
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Manager at Inside-Out Sports.
Some items we post could be used items traded in to the store.
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
Algebra my son... remember soh cah toa. The length of your stem is the hypotenuse, theta is 12 degrees and you want to calculate the length of the opposite side if this hypothetical triangle. sin12=x/100
I work out x to equal 20.79mm
HOWEVER, assuming you're already running this stem in the reverse position, the total height gain would be double that.. about 41mm
Discalimer: I haven't done math like this in 10 years since I left high school. Feel free to correct me noble slowtwitchers.
Don't forget to unclip!
I work out x to equal 20.79mm
HOWEVER, assuming you're already running this stem in the reverse position, the total height gain would be double that.. about 41mm
Discalimer: I haven't done math like this in 10 years since I left high school. Feel free to correct me noble slowtwitchers.
Don't forget to unclip!
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [ckufen]
[ In reply to ]
Should have known that Todd would have a cool little applet like this to figure this out. Thanks for sharing.
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [Armstronium]
[ In reply to ]
All right. Next question...and yeah, I admit this is dumb but is a "flipped" 12 degree stem then become -12 degrees?
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
That's what I would assume.
Don't forget to unclip!
Don't forget to unclip!
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
No. The stem angle is measured relative to the steerer tube, so until you take into account the angle of the headtube, you're still dealing with all of your angles in a rotated coordinate system. Since most road bike head tube angles are pretty close to 73 deg, a stem of -17 degrees will be close to "flat" (i.e zero degrees in the earth coordinate system), whereas a "0 degree stem" would actually point up 17 degrees above horizontal in the earth coordinate system. You can do trig equally well in both coordinate systems, but it's just much more useful to have the "stack"/"reach" deltas in X-Y than it is in some system using the steerer tube as the reference axis.
The fit calculators that others have posted will do this for you.
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The fit calculators that others have posted will do this for you.
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I tweet!
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
On a 100m stem? It will go up a bloody lot.
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [hayai_240]
[ In reply to ]
hayai_240 wrote:
http://yojimg.net/bike/web_tools/stem.php
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [ckufen]
[ In reply to ]
or you could just not leave the site. amazing everything here on slowtwitch if you just nose around a little ;-)
Dan Empfield
aka Slowman
Dan Empfield
aka Slowman
Re: Flipping a 12 degree 100m Stem - Anyway to know how much it will go up? [JimMoss]
[ In reply to ]
Assuming a 72° steering tube and flipping from 12° up to down
39.55mm Down
12.85mm Longer
39.55mm Down
12.85mm Longer