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  #1  
Old 06-08-2019, 02:24 PM
scottcw2 scottcw2 is offline
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Seat tube or top tube length more important all else equal?

I usually ride a 58-58.5 c-c square frame. I am considering a frame with a 61.5 c-c seat tube and a 58 cm c-c top tube.

I'm thinking that reach is the more important measurement here as I can always drop the saddle by ~3cm and adjust the fore-aft of the saddle to match the reach of my other bikes.

Am I correct or off base that the TT length is more critical than ST if all else is equal?
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  #2  
Old 06-08-2019, 02:40 PM
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Tickdoc Tickdoc is offline
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Quote:
Originally Posted by scottcw2 View Post
I usually ride a 58-58.5 c-c square frame. I am considering a frame with a 61.5 c-c seat tube and a 58 cm c-c top tube.

I'm thinking that reach is the more important measurement here as I can always drop the saddle by ~3cm and adjust the fore-aft of the saddle to match the reach of my other bikes.

Am I correct or off base that the TT length is more critical than ST if all else is equal?
Depends on your flexibility and what position you are comfortable riding in. TT is harder to adjust to fit than ST.
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  #3  
Old 06-08-2019, 02:50 PM
giordana93 giordana93 is offline
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Quote:
Originally Posted by scottcw2 View Post
I usually ride a 58-58.5 c-c square frame. I am considering a frame with a 61.5 c-c seat tube and a 58 cm c-c top tube.

I'm thinking that reach is the more important measurement here as I can always drop the saddle by ~3cm and adjust the fore-aft of the saddle to match the reach of my other bikes.

Am I correct or off base that the TT length is more critical than ST if all else is equal?
you never adjust saddle fore/aft to correct reach, period

a taller frame will generally have the handlebars higher, so if you need your bars on the higher side, should be fine; if you like them relatively low compared to the seat, then think again about this one

finally top tube length also is dependent on seat tube angle when setting up reach. a slacker sta will need a longer TT to have the same reach as a steeper sta
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Old 06-08-2019, 04:45 PM
Peter P. Peter P. is offline
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Top tube length is more important because you have a narrower range of adjustment via stem length, while keeping things proportionate.

Seat posts have a much greater range of adjustment, all but ensuring you can set seat height properly.
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  #5  
Old 06-08-2019, 05:37 PM
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Elefantino Elefantino is offline
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Stack and reach are becoming the measurements of choice for many manufacturers and fitters.
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  #6  
Old 06-09-2019, 04:41 PM
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charliedid charliedid is offline
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Quote:
Originally Posted by giordana93 View Post
you never adjust saddle fore/aft to correct reach, period

a taller frame will generally have the handlebars higher, so if you need your bars on the higher side, should be fine; if you like them relatively low compared to the seat, then think again about this one

finally top tube length also is dependent on seat tube angle when setting up reach. A slacker sta will need a longer tt to have the same reach as a steeper sta
this
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  #7  
Old 06-10-2019, 02:11 PM
John H. John H. is offline
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Big Bike

Your assumption and approach is flawed.

Not to say that the bike won't work- But here is the decision tree to follow.

1.) Can you achieve ideal saddle position (saddle height and setback).
2.) Can you find a stem that yields ideal reach and drop with the ideal saddle position.
3.) Does the bike ride and feel "right" when setup as needed. Often times a too big bike can handle weird, and certainly might look weird. Some care about this more than others.
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  #8  
Old 06-12-2019, 07:46 PM
ultraman6970 ultraman6970 is offline
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Ultra agrees with giordana... but doesnt mean it cant be done because it can be done the problem is that the fit will look weird, tiny guy in giant frame.

With some riders, they wont notice the way a bike handles correctly and they dont care if the frame is too big. The other issue is angles, a big frame in a small guy will handle weird but if the thing is lets say a classic 75 degrees italian bike probably the dude wont notice anything but do the same in a colnago c50 the bike will handle horrible,

So it depends of the bike aswell... For example the OP mentioned a lot of extra seat tube in the new frame but same top tube, I say... try it it could work just fine... but put me in that same frame and i will end up putting my legs between the frame to be able to pedal.
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