# Can anyone with a 56 or 58 cm Synapse help me with a measurement?



## Rob (Mar 3, 2004)

I am looking for the horizontal distance from the center of the top of the bar (where the seam in the stem is) to the center of the seat post. See pic below. If you have a flipped stem or a longer or shorter one than stock, let me know. I am looking for model year 2011 numbers. I don't know how previous years would compare. Also, you may not be able to measure this unless your saddle is a bit higher than your bar. 

Thanks to anyone who can help.


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## Bob Ross (Apr 18, 2006)

The measurement you're asking for will be impacted by the length of the stem, which is _not_ standard on a 56 or 58cm frame.


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## erict (Apr 4, 2011)

The seat tube angle and the head tube angle for the 56 is different than the 58 as well. On a 58 cm frame, the angles are the same, so the difference between the center of the steerer tube and the center of the seat tube should be 58, and the difference several cms higher would be the same 58 cm. The measurement you are looking for on a 58 cm frame should, in theory, be 58 cm + stem length.

Inquiring minds want to know what you want this measurement for.


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## Rob (Mar 3, 2004)

erict said:


> The seat tube angle and the head tube angle for the 56 is different than the 58 as well. On a 58 cm frame, the angles are the same, so the difference between the center of the steerer tube and the center of the seat tube should be 58, and the difference several cms higher would be the same 58 cm. The measurement you are looking for on a 58 cm frame should, in theory, be 58 cm + stem length.
> 
> Inquiring minds want to know what you want this measurement for.


Just comparing to my current bike to see which might fit me better. I think the 58 may be a bit too big and the 56 too small. Nobody around here has either size. As you said, the 58 should be pretty easy to figure but the 56, with its different head and seat tube angles will be harder to figure but should be a little less than top tube + stem. I was wondering how much less. Trying to see if I am more likely to go 58 + shorter stem or 56 + longer stem, etc...


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## kattywhumpus (Aug 5, 2008)

Rob said:


> I am looking for the horizontal distance from the center of the top of the bar (where the seam in the stem is) to the center of the seat post. See pic below. If you have a flipped stem or a longer or shorter one than stock, let me know. I am looking for model year 2011 numbers. I don't know how previous years would compare. Also, you may not be able to measure this unless your saddle is a bit higher than your bar.
> 
> Thanks to anyone who can help.



679.44mm on my stock 2011 58cm synapse...


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