# 2013 Tarmac stack



## designair (Jul 8, 2005)

Anyone know in size 56cm?


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## PJ352 (Dec 5, 2007)

Frame stack is measured from center of BB to top of head tube, so you could measure any Tarmac and (assuming the same fork length) simply account for the difference in HT lengths to get your number.

I'd be curious to know why you're asking/ what you're trying to determine. There may be other/ better ways to get similar information.


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## helios (Jul 22, 2010)

564mm
Specialized Bicycle Components


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## PJ352 (Dec 5, 2007)

helios said:


> 564mm
> Specialized Bicycle Components


That's odd. After you posted this I went back to the geo charts for some 2013 Tarmacs (I checked the low end model previously). 

Turns out they don't list reach/ stack till the Expert model and up. Apparently lower end buyers don't concern themselves with such things. 

OP: I'd still be curious what you're trying to determine. If you're using stack alone to compare to another bike, it may not tell you all you'll need to know re: fit.


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## helios (Jul 22, 2010)

Actually, that is the stack for a 56 *SL4*; lower end models are that not SL4s will have a different stack. 

But IMO stack/reach is the correct way to compare bikes. Comparing TT/ST/HT between bikes is meaningless if you don't take different HT/ST angles as well. Skipping to stack and reach tells you what you need to know, then it's just a matter of stem/spacer to put the bars in the right place.


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## helios (Jul 22, 2010)

56cm SL3s have ~575mm of stack IIRC. I also BELIEVE (not 100% on this) the lower models, as well as the Allez, are based on SL3 geo.


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## PJ352 (Dec 5, 2007)

helios said:


> Actually, that is the stack for a 56 *SL4*; lower end models are that not SL4s will have a different stack.


That would only hold true if the geo changed in some way affecting stack - mainly, HTL. I didn't check each model, but believe Tarmacs share the same geo across the model line. 

Still, buyers at all price points may be curious about that measurement, so an odd exclusion, IMO. 



helios said:


> But IMO stack/reach is the correct way to compare bikes. Comparing TT/ST/HT between bikes is meaningless if you don't take different HT/ST angles as well. Skipping to stack and reach tells you what you need to know, then it's just a matter of stem/spacer to put the bars in the right place.


I completely agree with this, _when comparing like models_. Dissimilar models may introduce variances that change the equation.


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## helios (Jul 22, 2010)

What do you mean by "like" and "dissimilar" models?


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## helios (Jul 22, 2010)

I think the reason stack and reach are not shown on the geo charts for the lower models is that they are, again, based on SL3 geo. When the SL3 was current for even S-Works bike stack and reach were not shown on the geo chart. Cervelo has been using the stack and reach concept for years and years, but no one else really has until the last maybe 2 years. I don't think Specialized ever really took the time to make an official measurement for those bikes, now that their "second-tier" relative to the SL4 it's probably not a priority.


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## PJ352 (Dec 5, 2007)

helios said:


> What do you mean by "like" and "dissimilar" models?


A frame stack measurement only considers the bikes frame. Anything outside of that has the potential to change fit parameters, one example being fork length.

Another example would be comparing a bike with an integrated headset versus non-integrated. The lower bearing stack height of the latter would need to be added to determine the correct frame stack height.


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## PJ352 (Dec 5, 2007)

helios said:


> I think the reason stack and reach are not shown on the geo charts for the lower models is that they are, again, based on SL3 geo.


IMO that's kind of a moot point. Whether someone calls a frame SL, SL3, 4 or just a Tarmac, the buyer may want the additional info. 

As I mentioned, considering the measurement, most changes (tubing diameter, being one example) don't affect stack.


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## helios (Jul 22, 2010)

PJ352 said:


> IMO that's kind of a moot point. Whether someone calls a frame SL, SL3, 4 or just a Tarmac, the buyer may want the additional info.
> 
> As I mentioned, considering the measurement, most changes (tubing diameter, being one example) don't affect stack.


The SL-2-3-4 progression are different iterations of the Tarmac. Whether the tubing diameter, to use your example, meant the the geo MUST change is irrelevant; the geo DID change. Therefore if you're a discerning consumer interested in things like geometry of the bike, a Tarmac (SL2) is not a Tarmac (SL3) is not a Tarmac (SL4). Make sense?


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## designair (Jul 8, 2005)

PJ352 said:


> That's odd. After you posted this I went back to the geo charts for some 2013 Tarmacs (I checked the low end model previously).
> 
> Turns out they don't list reach/ stack till the Expert model and up. Apparently lower end buyers don't concern themselves with such things.
> 
> OP: I'd still be curious what you're trying to determine. If you're using stack alone to compare to another bike, it may not tell you all you'll need to know re: fit.


I ride a old Giant time trial that doesnt have a top tube so I am not sure what size roadie would be best. I rode a Venge, lowest model, during a demo and the bike felt terrible. Do not recall size but do remember i felt way too stretched.

Was asked to race this upcoming season and over the weekend a current team member let me try his 2013 Tarmac Pro. I am @ 5'11-6' and he said hes 6'2"
bike was 56 with a 130mm -17 degree stem. The bike looked way too aggressive for me.
To my surprise the bike felt great. 



PJ352 said:


> OP: I'd still be curious what you're trying to determine. If you're using stack alone to compare to another bike, it may not tell you all you'll need to know re: fit.


Yes, I would like to compare Geo to Cannondale who list Stack and reach on website


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## PJ352 (Dec 5, 2007)

helios said:


> The SL-2-3-4 progression are different iterations of the Tarmac. Whether the tubing diameter, to use your example, meant the the geo MUST change is irrelevant; the geo DID change. Therefore if you're a discerning consumer interested in things like geometry of the bike, a Tarmac (SL2) is not a Tarmac (SL3) is not a Tarmac (SL4). Make sense?


My point is... tubing diameter/ shape, layup, naming conventions are _all _irrelevant to convo's re: frame stack, because they can change without geo changes. And without geo changes, frame stack won't change.

Re: your 'discerning consumer' comment, I'm an avid cyclist who owns (and has owned) a few bikes - including an '08 Tarmac Comp and an '11 Tarmac Pro. I didn't _only_ care about frame stack when I bought the Pro, but not the Comp. :wink5:


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## designair (Jul 8, 2005)

helios said:


> Actually, that is the stack for a 56 *SL4*; lower end models are that not SL4s will have a different stack.
> 
> But IMO stack/reach is the correct way to compare bikes. Comparing TT/ST/HT between bikes is meaningless if you don't take different HT/ST angles as well. Skipping to stack and reach tells you what you need to know, then it's just a matter of stem/spacer to put the bars in the right place.



What i was thinking


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## designair (Jul 8, 2005)

helios said:


> 564mm
> Specialized Bicycle Components


Geez, I was wondering where folks were seeing stack because it is not listed here where i was looking.

Specialized Bicycle Components

Thanks


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## helios (Jul 22, 2010)

OP - you're on the right track, SL4 and CAAD10/SuperSix/EVO stacks are pretty close, well within what can be corrected with minimal spacers. The Venge throws a curve ball in that its stack includes the headset dust cap because it's "integrated" whereas the others (SL4 and Cannondale models) do NOT include the headset dust cap. 

SL4 comes with a standard ~8mm dust cap but most Cannondales come with a taller ~15mm verson (there's a shorter version underneath the tall one). Just a couple things to keep in mind when looking at the raw numbers.


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## PJ352 (Dec 5, 2007)

designair said:


> I ride a old Giant time trial that doesnt have a top tube so I am not sure what size roadie would be best. I rode a Venge, lowest model, during a demo and the bike felt terrible. Do not recall size but do remember *i felt way too stretched*.
> 
> Was asked to race this upcoming season and over the weekend a current team member let me try his 2013 Tarmac Pro. I am @ 5'11-6' and he said hes 6'2"
> bike was 56 with a 130mm -17 degree stem. The bike looked way too aggressive for me.
> To my surprise the bike felt great.


While it's true that the lower you go with drop, the more reach increases, be aware that reach equates to feeling stretched out, not stack. That has more to do with drop.

As far as sizing/ height, there's more to pinning down your sizing requirements that that. You have to factor in proportions, fitness/ flexibility, riding preferences (among other factors). Point is, we can't size you over the internet. You have to work with a knowledgeable fitter and test ride the bikes. 



designair said:


> Yes, I would like to compare Geo to Cannondale who list Stack and reach on website


You don't say which C'dale model you're considering, but if the 56cm Tarmac felt great and the C'dale is similar (both race bikes) you can use the Tarmac as a baseline and compare frame reach/ stack of each. Just keep in mind that they're ballpark numbers and won't translate literally in fit (reach/ drop).


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## designair (Jul 8, 2005)

PJ352 said:


> While it's true that the lower you go with drop, the more reach increases, but just be aware that reach equates to feeling stretched out, not stack. That has more to do with drop.
> 
> As far as sizing/ height, there's more to pinning down your sizing requirements that that. You have to factor in proportions, fitness/ flexibility, riding preferences (among other factors). Point is, we can't size you over the internet. You have to work with a knowledgeable fitter and test ride the bikes.
> 
> ...


Yes i do understand. Comparing visually the supersix/evo and tarmacs I didn't know if the tarmacs had higher head tubes.


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## PJ352 (Dec 5, 2007)

designair said:


> Yes i do understand. Comparing visually the supersix/evo and tarmacs I didn't know if the tarmacs had higher head tubes.


If you're pretty much set on the C'dale, see if it might be possible to bring the 56cm Tarmac and ride it and the C'dale back to back. After tweaks, fit will likely be a wash between them, but (for a variety of reasons) you may find you prefer one over the other.

IME back to back test rides are a good way to determine that.


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## designair (Jul 8, 2005)

PJ352 said:


> If you're pretty much set on the C'dale, see if it might be possible to bring the 56cm Tarmac and ride it and the C'dale back to back. After tweaks, fit will likely be a wash between them, but (for a variety of reasons) you may find you prefer one over the other.
> 
> IME back to back test rides are a good way to determine that.


point taken, as i wasn't sure if one brand vs the other would be better fit wise.

Not set on one brand, but looking for the best option for mostly fast crit racing.


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## PJ352 (Dec 5, 2007)

designair said:


> point taken, as* i wasn't sure if one brand vs the other would be better fit wise.*
> 
> Not set on one brand, but looking for the best option for mostly fast crit racing.


Depends on the brands/ models (and sometimes, model years) of the bikes being compared. 

The C'dale Supersix and Tarmacs are very close in geo, so fit will be as well.

Both are nice bikes, IMO. No bad choice here, just personal preference.


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