Friday I spent a whopping $15 on this poor neglected '89 LeTour -




- which I am planning to mothball until next year's Clunker Challenge, because I have already over-indulged in this year's edition. The tubing decal at first blush leads me to think this is built of plain-gauge True Temper 4130 -




- but it feels really, really light. I do understand, though, that a 26.6 mm seatpost in a seat tube with a 28.6 mm diameter means I'm looking at roughly a .9 mm wall thickness, and traditionally seat tubes are single-butted - but the stated 1989 catalog weight for this bike is 25 lbs stock. The 1989 catalog description is "True Temper Full 4130 Chrome-Moly Frame."

The 1990 catalog describes it as "True Temper Double Butted Chrome Moly," and also gives a weight of 25.1 lbs with a 26.6 mm seatpost.

So - are they the same frame? Are both '89 and '90 double-butted tubing? Please help me, this is what we call a "splinter of the mind," and it will quietly gnaw at me.