I'm trying to think of the tube as a structure. To me if one is dealing spar tapering, in this kind of use, it would be totally gradual. I don't even really think a spar is the right model for the major loads, which seem to be more longitudinal with the tube. You see this kind of thing in other tubes, for instance tapered fork blades where the excess material is all there in thickening of the tube, which seems pretty random, and more a manufacturing issue that a perfect structure. Another thing on the main frame tubes is that even were several tubes are available for sizing the butted tube is fairly random in how it all comes out structurally. It seems to me that the whole thing is more explainable on the grounds of heat. There, just about everything makes sense, though the seat tube is a little hard to drop easily into either camp. Anyway, in the real world there doesn't have to be just one explanation.

Part of the deal is that we buy into some overarching theory, that is patchy at best, and then we feel great about our fabulous purchase. As we should. So my suggestion, no less rigorous, to the guy who wants to buy a straight gage tubeset, is to feel good about it. And here is the technical package for doing that: As he mentioned, tube ruggedness; And also think of the joinery as being optimized efficiently, and the tubing being a wall thickness update without the inefficiency of the butts. It is as good a story as the one behind lugs.

If you want to get a lugged frame, which I think is fabulous, then buy into the idea that: The design and contouring of all those heraldic forms is awesome; that lugs and butts stop the frame from catching on fire during the build, as only lugs can; and that the butts are a major source of weight reduction as opposed to added weight that it there only because the tubes are being cooked so long. Ok, I probably went a little far...


In general TIG tubes are conventionally sized, in part because it gives the option to use the tubes in either method, but also probably because there is minimal disadvantage to having the extra beef there anyway, and that goes for machining as well. I do think it is probably possible to make a tube that is totally optimized to TIG, and it might have a different properties. We are nearly there, given the popularity of TIG, but I think the dual use thinking still prevails.

What is different in this case is that we are talking a much bigger rider, so arguably he would need a stouter tubing anyway. So it would be butted with an .8 in the middle, not a .6. So it really becomes a non-issue as to whether the whole tube is just straight .9, because we know there are no crazy difficulties welding .9, so why bump it up .1 extra mm for heat or weld reasons. Now if we were discussing 9/6/9 tubing vs straight .6 (hard stuff to find in any case, in all the sizes) The case for straight .6 is not really there. It would be delicate to weld. Last time I looked it was more expensive than plain jane 9/6/9, etc... I would kinda like to try making a straight .6 main tube bike, but as I say it costs more for me, and I am too heavy anyway. But one can weld straight .6, and that is why it is there, it can be welded oxy, or TIG, and no butts are required. Butts are kind of a cycling thing.

Nice Bike! I'm only 6'1", so I am not for the most part inconvenienced by my height. I still wouldn't mind being tall enough to ride that bike for a day.