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Merlin Agilis Geometry Questions

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Merlin Agilis Geometry Questions

Old 11-11-19, 11:18 AM
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amerikaner
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Merlin Agilis Geometry Questions

Hi All, hopefully folks with a Merlin Agilis can help. I'm trying to figure out the sizing on a M vs M/L...Seems like the 2002 and later Agilis' had the hourglass head tube, but the 2001 had a less dramatic shape. See pic below:



I found the 2002 catalog with geometry from retrobike, but is the earlier (pic on left) have the same geometry? I'm thinking no as the head tube is longer. Also, does Merlin use "Actual" or "Effective" top tube measurements?

The 2002 catalog lists:

virtual size = Virtual Seatpost??? or is this Effective TT???
frame size (c to c) = Seatpost
top tube length = Actual???

Anyone have the 2001 Catalog?

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Old 11-11-19, 01:20 PM
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With only one TT length posted, it will be a horizontal measurement. The headset is integrated and the HT length is listed. That's no different than any other modern frame.

It is odd that so many seat tubes are the same length.
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Old 11-11-19, 02:58 PM
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Ok, thanks...I agree it's interesting the seat posts are the same, definitely a factor of the angles. I wonder how much of an impact the hourglass headtube has on the geometry...still searching for a geometry chart from 2000 or 2001.
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Old 11-11-19, 03:42 PM
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Originally Posted by DaveSSS View Post
With only one TT length posted, it will be a horizontal measurement. The headset is integrated and the HT length is listed. That's no different than any other modern frame.

It is odd that so many seat tubes are the same length.
I never thought about this before but it means that the rear triangle doesn't change with frame size. So Merlin only needs to build one rear triangle for all frame sizes. If this works riding-wise, smart! Manufacturers have been building one steel fork with a long steerer and cutting it to size before threading a long time. They'd use different head angles to get the desired riding characteristics for the different frame sizes with that one fork and rake.

Ben
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Old 11-11-19, 04:00 PM
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So if the chainstay, seat tube are the same but the angle changes by .5 degrees would the seat stays very in length?
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Old 11-11-19, 04:53 PM
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Only the chain stays and the seat tube would remain the same. The seat stays would change with the STA.

The bell shape has nothing to do with the fit. Just like a carbon bike the head tube length is listed and the headset sits inside. The pictures show a very low headset top, probably 5mm. Most are 15mm these days, but that can be changed as desired.
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