Framebuilders - Source for conical seat & downtube?
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DannoXYZ
10-16-09, 02:18 AM
I'm building a crit-bike and would like to feature conical tubing similar to some of the Serotta models. For the seat-tube, looking for something that's 28.6mm up top and expands to 31.8-34mm at the bottom. Something similar for the downtube, perhaps 31.8 going to 34mm.
Anyone know of a source for a seat-tube like this?
TIA
Live Wire
10-16-09, 11:35 AM
Joe B has a Deda downtube that would fit the bill- a few years ago, I had a couple of Tange Prestige st's that flared like that, but no idea on where to find nos stuff like that now.
Nessism
10-16-09, 09:21 PM
Yea, Joe has Zero down tubes like that and a BB shell to match if you want to use lugs - seat tube size is 28.6. These tubes are very light so honestly, I'm not sure if they are the best choice for a crit frame where stiffness is important. You might be better off going with a 35mm non-tapered down tube and 31.75" seat and top tube. The frame will still be sub 4 lbs and plenty stiff for crits.
DannoXYZ
10-21-09, 02:47 AM
The larger diameter should actually more than make up for the lighter weight. I was thinking of laterally ovalizing the tubes so they'd be the same diameter on the minor-axis all the way down. And adding external gussets as well.