Stack and Reach: Why It's Your Best Friends

(yes)
Less steep, less vertical.

good article: http://www.bikeradar.com/us/gear/article/your-top-tube-length-is-irrelevant-50174/

What does it mean by an offset seat-tube?

Although I agree with the broad thrust of the article, doesn't the method blur the science?

Using a measurement that includes the, irrelevant, rear wheel/tyre doesn't make sense.

Perhaps I'm reading it wrong?

The article is a bit fuzzy and confusing, I think my original one make more sense (i am biased after all!).

The measurement is:
(wall to bars) - (wall to bb)
Giving you the distance between the bb and the bars, the subtraction negates the size of the wheel/tyre and length of chain stays.
Unless I've completely misunderstood what you're getting at

This is correct

Unless I've completely misunderstood what you're getting at

Nope, you're spot on!

My fault for browsing the article, rather than reading it.

Can stack and reach be considered exchangeable at all? If you found a frame/stem combo that gave you 30mm more stack yet 30mm more reach than what you currently have, would these two theoretically cancel eachother out?

Wut?

If you put enough spacers on to get exactly 30mm more stack and lengthened the stem enough to get 30mm more reach, would the two cancel eachother out?

If you found a frame/stem combo that gave you 30mm more stack yet 30mm more reach than what you currently have, would these two theoretically cancel eachother out?

If you put enough spacers on to get exactly 30mm more stack and lengthened the stem enough to get 30mm more reach, would the two cancel eachother out?

It sounds like you’d need inverse spacers and a 30mm shorter stem.

http://yojimg.net/bike/web_tools/stem.php

Rookie stack question, if a frame has a listed stack height but uses an external headset can i add the headset top section height dimension to the stack total when comparing it to a frame that has an integrated headset?

yes and thats why you should buy my dart ;)

God-dammit! sending pm...

Ok I'm looking for relief from anxiety and confusion. I've established that my all city big block (size 58), which I really like, has stack ~595mm and reach ~420mm. The top tube is 585mm. The seat and head tube angles are 74 degrees. Ok, fine. But now I'm looking at geared bikes and for instance a surly straggler size 60 has a stack of 609mm and reach 412. So pretty close. But the top tube is 610mm, ie 25mm longer than the big block. Is this due to the slacker seat and head tube angles of 72 degrees? And, my real question: can I really trust the reach measurement and disregard the top tube length?

The Reach is more precise and accurate than the top tube.

It’s due to the seat tube angle (as mentioned in like, the first post of this topic!).

TL:DR; it will fit if your saddle is set far bsck/have a layback seatpost.

It’s as good as the person doing the measuring. Combined with a stem geometry tool like the one Amey posted you can make a 52 cm Bowman Pace and a 54 cm Specialized Allez put your bars within 1mm of each other.

it will fit if your saddle is set far bsck/have a layback seatpost

On the current bike, you mean? Yes, layback post and saddle set back about 2/3 of the way. Thanks. Read the first post again and the article upthread, makes more sense now.

In that case the Surly will fit you well, worse case is maybe an in-line post.

If trying to calculate stack and reach in the link do I use effective or actual top tube length?

http://www.bikegeo.net

Bumping this because it should be a quick enough question to not start something new.

My old road bike has a stack of 540mm, reach is 405mm.
Now I'm eyeing a new bike and I'm stuck between two sizes.
Medium size has a stack of 577, reach 385.
Large size has a stack of 596, reach 394.

I rode with a 80mm stem, bars have 77mm reach, which was all pretty good. Didn't feel stretched.
So the problem wasn't the reach of the bike, but I did not feel super comfortable as I felt like I was sitting pretty deep.

That would make the L a decent fit, as the reach is a bit shorter which gives me a longer stem, fine, but I'm not sure if going from a stack of 540 to 596 is too much.

Any suggestions? Overthinking it?

https://geometrygeeks.bike/

suggestions?

Get the L and a pro looking-17 deg stem?