Framebuilders - Top tube length question

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Seattle_Jerry
04-06-09, 01:50 PM
While I'm saving for a custom frame I've been searching the usual places for a vintage frame to tide me over.
My question is that after doing one of those online measurement programs it suggests a 59.5 top tube.

Does that mean 59.5 including stem length or add some stem on top of that to fine tune the fit?

It was actually 57.5 for touring up to 59.5 for road. Ultimately I will need to get a custom though as I have to ride a too tall bike to get the top tube length on an off the shelf frame.

Whats the shorter top tube do for touring?

Thanks,

Jerry

Six jours
04-06-09, 02:02 PM
When someone refers to top tube length it is generally understood that he means the length of the tube measured from the center of the seat lug to the center of the head lug.

It is also generally held that a touring rider will prefer a more upright position for his upper body, achieved by bringing the handlebars closer to the rider.

I wouldn't let the internet give you cast-in-stone numbers, FWIW. I'm sure whatever calculator you have used has given you fine ballpark numbers, but if you go to your framebuilder insisting that some website said 59.5 and you won't accept 59.0 or 60.0 you are liable to get laughed at, if not forcibly ejected.

HTH!
Seattle_Jerry
04-06-09, 06:37 PM
Oh No...I'm not that foolish. I plan to be properly fitted when I get one built. I'm just wondering if the formulas that go off of inseam, ground to collar bone and arm length and spit out a top tube length...that seems like it would mean frame top tube c to c. But then the stem adds more...a lot more in some cases. So I am making the assumption that the stem is not figured into that calculation because the top tube length then would be really short. Just wanted verification.

I guess what I'm doing now is a trial and error extended road test on various lengths to see what feels good/right

Six jours
04-06-09, 06:49 PM
Ah. Got it, and sorry for talking down to you.

I've never seen any calculator that provided TT length other than in c-c, but what I haven't seen is a lot. I am sure your assumption is correct.