Originally Posted by
seeker333
I googled and instantly found
geometry figures for Specialized Sirrus Comp at the top of the list. You may have to work harder to find geometry info on older bike.
Disregard stack and reach. Compare effective top tube (ETT) length between your wife's drop bar bike and LHT. If you intend to build LHT with flat bar, then you will need ~50-70mm more reach (ETT+stem length) for comparable fit. On a LHT this will likely result in an undesirably high standover height (SH). Bear in mind that 26" LHT SH is based on ~1.37"/35mm tires (628mm diameter), so if you fit larger tires than this the SH will be even greater. Refer to diagram to measure ETT:
https://www.bikecad.ca/effective_top_tube_length
Thanks for the information and for finding the geometry page. It looks the same as her model. I cannot understand some of your information; but in any case her bike now is the Specialized flat bar and her new bike will be the surly with drop bars.
Speicalized refer to "TOP-TUBE LENGTH (HORIZONTAL)" I don't know what this means vis-a-vis Surly's "Top Tube Length" and "Effective Top Tube Length"
Can any one clarify that?
Cheers