# Effective top tube question...



## MCF (Oct 12, 2006)

How can two frames that have the same head tube angle and seat tube angle and different top tube lengths have the same effective top tube length? Comparing my '06 Allp d huez geometry to the '08 Zurich geometry, the '06 has a 1/2" longer top tube length, head tube angle and seat tube angle are the same between the two, yet effective top tube length is the same...interesting...


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## RoadCube (Nov 22, 2006)

Head tube length maybe different. My 07 BA has a way long head tube and I compared the 06 Alpe 57 to my 07 BA 57
RC


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## VaughnA (Jun 3, 2003)

One can be a compact, another a traditional or semi compact frame.


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## kneejerk (Feb 2, 2007)

As VaughnA said!........ One of them is likely a "sloping" top tube design the other less sloping or horozontal top tubed.


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## C-40 (Feb 4, 2004)

*effective...*

The term effective is a misnomer, which really means horizontal. When comparing the fit of two frames, the sloped TT length is meaningless. I don't know why any company lists the sloped TT length.


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