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~~~~~~~~
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great news, glad to see it standardized.
a question for DT, I recall that the front center measurement (what it was called before reach and stack), was measured to the bottom of the headtube, did I have it wrong, if not why the change to top of the head tube? Is it because it's now been broken down into two seperate measurments where as front center was only the reach but to the bottom before?

edit: okay, read it more carefully this time. What was front center measurements before are now called reach but will actually be shorter than the old FC numbers since it's measured to the top now?
 

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I'm more of a dog person
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Turner and Transition

if you read the article, it sounds like Transition were the ones who actually came up with the idea of making it an industry standard. Not taking anything away from DT cause he was already using a version of it with the DHR, but let's give credit where credit is due. Both DT and Kyle/Kevin are the pioneers here.
 

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airwreck said:
great news, glad to see it standardized.
a question for DT, I recall that the front center measurement (what it was called before reach and stack), was measured to the bottom of the headtube, did I have it wrong, if not why the change to top of the head tube? Is it because it's now been broken down into two seperate measurments where as front center was only the reach but to the bottom before?

edit: okay, read it more carefully this time. What was front center measurements before are now called reach but will actually be shorter than the old FC numbers since it's measured to the top now?
Front-center measurement is actually measured from the bb center to the front axle center...fyi :)
 

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Bite Me.
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I have a question - assume that the reach and stack are the same on two bikes - one bike with a 71 degree seat tube angle and another with a 73.5 degree seat tube angle - the reach and stack will be the same since the BB doesn't move relative to the center of the head tube (the seat tube just "rotates" around the BB) - the two bikes will have two very different effective top tube lengths, especially as the frame size gets bigger, but the R & S won't tell you that - so how do we know which bike fits better?
 

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cutthroat said:
I have a question - assume that the reach and stack are the same on two bikes - one bike with a 71 degree seat tube angle and another with a 73.5 degree seat tube angle - the reach and stack will be the same since the BB doesn't move relative to the center of the head tube (the seat tube just "rotates" around the BB) - the two bikes will have two very different effective top tube lengths, especially as the frame size gets bigger, but the R & S won't tell you that - so how do we know which bike fits better?
Reach and Stack measurements are more relevant to gravity oriented bikes where the rider isn't sitting much (if at all) while pedaling, IMO. Others may disagree with me on that though.

I think for seated pedaling, the effective top tube is still an important measurement for the reasons you mention. Now, if manufacturers would just agree on how to measure that!

Not to burst anyone's bubble, but I'd hardly say 2 manufacturers agreeing on this measurement constitutes a "standard" at this point......although Shimano might disagree with me on that. :rolleyes:

EB
 

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cutthroat said:
the two bikes will have two very different effective top tube lengths, especially as the frame size gets bigger, but the R & S won't tell you that
I think that's kind of the point- those two bikes would list drastically different effective top tube length measurements (an inch or so probably), even though they would ride exactly the same for a given saddle-handlebar reach and saddle-bottom bracket height. Most riders work backwards towards their seating position based primarily on the bottom bracket position, and to some extent the distance to the handlebars. A listed top tube length presupposes where the saddle will end up; how many riders actually use a zero offset post with the saddle centered perfectly on the rails?

I imagine the manufacturers will still provide top tube lengths for those used to fitting bikes solely by that dimension, but the new "reach" measurement is actually a much more precise way of doing so.
 

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ebxtreme said:
...I'd hardly say 2 manufacturers agreeing on this measurement constitutes a "standard" at this point......although Shimano might disagree with me on that.
Don't be ridiculous. How often does Shimano get a 2nd mfgr onborard before declaring one of their new "standards"?

:D
 

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ebxtreme said:
Not to burst anyone's bubble, but I'd hardly say 2 manufacturers agreeing on this measurement constitutes a "standard" at this point......
EB
In my line of work, we have a joke....
"I like standards so much, I've made my own!" :rolleyes:

Anyways... I still prefer the terms "girth" and "length" when referring to my steed :ihih:
 

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miles e said:
. A listed top tube length presupposes where the saddle will end up; how many riders actually use a zero offset post with the saddle centered perfectly on the rails?/QUOTE]
If I understand the "Virtual" Top Tube measurement it's based on the distance from the center of the HT to the center of the Seat Tube along an imaginary line parallel to the ground. That's what Turner has been using. That tells me much more about cockpit fit than Reach and Stack which leaves the seat tube position out of the equation. Obviously, saddle position and seat height result in minor variations in the final fit, but as an objective standard for measuring the length of the top tube, virtual TT length gets you more information. For me, TT length was always the most critical component of proper fit, and it was where I started, not backed into. Gravity bikes are obviously a different issue.
 
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