Note on Tange Infinity tubing
 

While browsing The Paterek Manual, a book about framebuilding, I ran across this note, in a "supplement" at the rear (page 342):

"Pg. 2-64
Tube sets; Tange has recently introduced the Infinity series of
tubing. This is a seamed tubing that has tapered walls rather than butted
walls. During coldworking, the seams nearly disappear from sight and the
tube takes on almost the same strength properties as seamless tubing. Send
to Shimano for more information. The Infinity name comes from the concept
that the tubes do not have a starting or stopping point for the butt. In
effect, they are infinitely butted."

This book is not dated, but it looks like it was self-published, in the early 80s. I don't have a paper copy, just the scanned version that is available at http://icelord.net/bike/

What's interesting, apart from the technical claim made, is that this seems to be a "late-breaking news" addition to the basic text, which includes a chart with Tange tubing on the referenced page. That chart includes Prestige, along with Nos. 1 through 5. So, if all this can be believed, Infinity was not a precursor of Prestige, but was introduced later. The note in the supplement before this one advises of another tubing newly available from Tange: "900."

there is infinite change in between a nickel and a dime, too.

ah, that sounded too harsh. I was just commenting on the marketing types stretching the concept to its limits. As I remember, Prestige was first, and Infinity was later. I could see the seam, though.

Infinity came no later than 84 as my Centurion is built with it. Certainly heavier than my 531 or Columbus SL bikes though it is a comfortable ride. And got to admit the Brooks B17 and high flange hubs have a bit to do with the weight as well. Will probably be taking that bike out this weekend.

Oh, I can see the seam too, in the seat tube of my Nishiki frame. But, at a slightly larger size than my 531C Raleigh, the Nishiki is only about 50 grams heavier. The frame is heavier, but the fork is lighter than those on the Raleigh.

I hope this question is not considered a thread hijack, that's not my intention.
Where does Tange 900 (double butted) fit into this picture, my guess is one step lower than Infinity. Is that correct?

Is 50 g significant in trying to judge whether the tubeset was the driving factor? What is the typical sample to sample weight variation between sequential production units of such frames?

Road Fan

My Shogun touring bike is infinity tubing, and doesn't feel all that light to me? It rides like a Lincoln though,
so I'm not complaining. I could barely see a seam when I had it stripped down for paint.,,,,BD

I double-checked, and the difference is actually 75 g, not 50. To be more accurate, the Nishiki frame weighs 160 g more than the Raleigh, while its fork is about 85 g lighter. My point was simply that the Infinity tubing is probably not that much heavier than the Reynolds 531C. And I have no idea how any sort of as-built weight variation information could be compiled at this date: the bikes we have available as a sample are different models, from different years, constructed in different sizes. Too many variables!

Yeah, Charles, we'd need a lot of access to a bike frame factory's production records, or enough experience with designing and building frames to have the craft knowledge. I was hoping such a unique person would chime in. My question was definitely to the community rather than to you!

Just to know what the variation is requires lots of data.

Road Fan

Thanks A.Winthrop, much appreciated.

Here's another almost-threadjack:
If Tange 900 was equivalent (more or less) to Tange 2, does that mean that Tange 1000 was equivalent (more or less) to Tange 1?