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Home > Forum > Triathlon Forum > Stack and reach from photo?

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Stack and reach from photo?
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asellerg
Jul 31, 15 21:47
Post #1 of 13 (2397 views)
Hey guys,

I crashed in my last race and unfortunately hadn't taken measurements of my new (read: several months old) position before the bike was mostly ruined. I do, however, have a photo of the bike straight on. Can anyone with PhotoShop access and expertise gather the measurements from the photo? I believe there's a way to set a reference measurement (e.g. wheel diameter) in the program and then measure other lines, but I don't know how to do it myself. I haven't decided if I'll buy a new frame (depending on if the old can be repaired) but will also take suggestions (Dimond? Trek SC?). Also, feel free to critique and/or ridicule my setup.


Coach at TriForce Triathlon Team: https://www.triforceteam.com
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Re: Stack and reach from photo? [asellerg] [ In reply to ]
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frenchieTT
Jul 31, 15 22:11
Post #2 of 13 (2384 views)
Print to scale your photo and use a good old ruler?

Not gonna be very accurate though as it depends on the angle at which you took the photo.
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Re: Stack and reach from photo? [asellerg] [ In reply to ]
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cyclenutnz
Aug 1, 15 0:58
Post #3 of 13 (2361 views)
We can calculate fairly well by knowing the configuration:
Can you confirm the following - Large frame with the carbon aerobar? Stem on 90mm setting and slammed down? Low stack (ie the warranty replacement) extension mount with pads in middle row?
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Re: Stack and reach from photo? [cyclenutnz] [ In reply to ]
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asellerg
Aug 1, 15 9:16
Post #4 of 13 (2271 views)
Cool! Yes it's at the 90 mm setting and the low stack is slammed completely down. The frame is actually a medium.
Coach at TriForce Triathlon Team: https://www.triforceteam.com
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Re: Stack and reach from photo? [asellerg] [ In reply to ]
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michaer27
Aug 1, 15 10:19
Post #5 of 13 (2244 views)
A good and free program you can use to measure distances, angles, areas and all sorts of other things that you don't need for this question is ImageJ. You can find it here:

http://imagej.nih.gov/ij/


I think it's relatively easy to use. You will need a known distance in the image, which could be wheel diameter (measured through the hub of course).
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Re: Stack and reach from photo? [michaer27] [ In reply to ]
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asellerg
Aug 1, 15 10:49
Post #6 of 13 (2226 views)
Awesome thank you, I will check it out!
Coach at TriForce Triathlon Team: https://www.triforceteam.com
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Re: Stack and reach from photo? [asellerg] [ In reply to ]
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beercity
Aug 1, 15 13:43
Post #7 of 13 (2158 views)
If you know axle to axle distance I can get you stack and reach.

Edit: Assuming 993mm axle distance, I got the following

617 Stack
476 Reach

I used Bike Fast Fit to figure those numbers.

I might be off a bit on pad placement but I think I am close

http://imgur.com/a/OHVKD

Also, you seat is 723mm above BB, and tip is about 20mm behind the BB. In case you needed that as well. Seat angle I can't get very accurate on.
Last edited by: beercity: Aug 1, 15 13:58
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Re: Stack and reach from photo? [beercity] [ In reply to ]
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asellerg
Aug 1, 15 14:46
Post #8 of 13 (2125 views)
You are awesome! The bike is in the shop now but if I get it back I'll double check the axle to axle distance. This at least gives me a place to start with a new fit. Thank you!
Coach at TriForce Triathlon Team: https://www.triforceteam.com
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Re: Stack and reach from photo? [beercity] [ In reply to ]
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Slowman
Aug 1, 15 14:54
Post #9 of 13 (2120 views)
those numbers are not stack and reach. but they might be pad x and y. and if they are, you'll want to stipulate whether it's to the back or center of the pad. my guess is you chose center (probably a wise move).
Dan Empfield
aka Slowman
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Re: Stack and reach from photo? [Slowman] [ In reply to ]
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beercity
Aug 1, 15 15:37
Post #10 of 13 (2106 views)
Slowman wrote:
those numbers are not stack and reach. but they might be pad x and y. and if they are, you'll want to stipulate whether it's to the back or center of the pad. my guess is you chose center (probably a wise move).

Thanks. Center of pad, best that I could approximate from the picture. I figured pad placement was what he was looking for considering the situation at hand.
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Re: Stack and reach from photo? [beercity] [ In reply to ]
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michaer27
Aug 1, 15 18:14
Post #11 of 13 (2067 views)
I checked out the image (http://imgur.com/a/OHVKD) and just wanted to point out that the lines are not parallel to the ground. If you look at the bike, the front (right) wheel appears to be higher than the rear (left) wheel. That is, the camera was tilted slightly. Therefore, a line parallel to the bottom of the photo is not parallel to the long-axis of the bike.

If my logic is right, that would mean that your measure of stack (or pad X) is off (maybe pad Y too). How far off will depend on how steep the deflection from horizontal is (it could be negligible or significant).
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Re: Stack and reach from photo? [asellerg] [ In reply to ]
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cyclenutnz
Aug 2, 15 2:56
Post #12 of 13 (1980 views)
asellerg wrote:
Cool! Yes it's at the 90 mm setting and the low stack is slammed completely down. The frame is actually a medium.

That calculates out to Pad XY 447,613 - to back of pad and including the cushion
Note that I'm working from measuring bars, not drawings, so there might be a couple of mm error.

A shiv is not really the right bike for you if you need to set it up like that. Speed Concept or a Cervelo would offer more room to adapt your position
Quote Reply
Re: Stack and reach from photo? [cyclenutnz] [ In reply to ]
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asellerg
Aug 2, 15 23:18
Post #13 of 13 (1892 views)
Yeah that's what Jim @ ERO had told me too. I was basically at the very limit of what the Shiv can do for me. I'll look into the Trek SC. Thanks!
Coach at TriForce Triathlon Team: https://www.triforceteam.com
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