Limber is in the tail of the rider, and Trek made different geometries fo r different purposes. I don't have the specs for the TX700 in front of m e, but I'm guessing it's the sport touring geometry with the 17 inch chains tays. If so, it will be a very good all around bike, perhaps a bit stiff er in the BB than most contemporary french 531 bikes, which usually (but no t always) means stiffer at the saddle too.
If however, your chainstays are 17.5 inches or more, then you have one of the touring geometry Treks, a different kettle of fish. Now it depend s when it was made. I had a '78 Trek 520 (Ishwata DB tubing) with 17.5 s tays and an Avocet Touring II saddle, and it was tremendously comfortable f or longer rides. Perversely, I didn't take it on many such because it sp orted stout wheels, fenders and racks, which ran the weight up and made m e feel slower. So it usually sat in the barn while a zippier bike got th e longer ride assignments. My butt suffered, but my ego as massaged. I sure miss that Trek.
I also had a late 80's Trek 720 in Reynolds 531c tubing. This was one of the Treks with the cast lugs and plug in stays, and chainstays stretched t o a voluptuous 18 inches. In my opinion, the tubing was too light for th is frame (25.5 inch seat tube) and the BB swayed abominably. Lots of aut o shifting and front derailleur rub under hard pedaling. But it was a co mfortable frame. The Trek 520 was a far better rider, and just as comfy. I sure don't miss that Trek.
The only thing vintage I've had that equaled the 520 in comfort while still being acceptably zippy was a Gitane Tour De France. Also nice long chai nstays, but the Gypsy had a stout enough DT and chainstays that the BB wa s adequately stiff. I rode the Gitane more than the Trek, probably bec ause the Gitane had a nice set of tubular wheels. Again, mega comfy, but not a featherweight in my frame size. If I had put the tubies on the Tr ek 520, it might have been a dead heat.
All three were more comfortable than the PX 10 I had. Don't know why, bu t Peugeot geometry and I didn't hit it off, at least for a '78 25 inch PX 1 0. It wasn't bad, just not as good as the Gitane and Trek 520. No dat a for Motobecane.
Of course the Treks will be easier to buy parts for, especially bottom brac kets, stems, seat posts and headsets.
And remember that all comfort factors may change radically depending on fra me size, your weight, wheel stoutness, tire width, barometric pressure, the phase of the moon, how you slept the night before, state of your hangover, purity of morals, etc etc. My advice: get one of each, swap wheels and saddles to be consistent and ride each several thousand miles for a fa ir comparison. You'll then have the best opinion, and have tons of fun i n the meantime.
Manhattan, Kansas, USA
From: Wayne Sulak <email@example.com>
Subject: [CR] Vintage Treks vs PXs, Motobecanes & Gitanes
Date: Monday, February 2, 2009, 5:18 PM
>Date: Mon, 2 Feb 2009 14:39:23 -0800
>From: Jon Spangler <firstname.lastname@example.org>
>.Subject: Re: [CR] Next project?
>Cc: Todd Grantham <email@example.com>
>Content-Type: text/plain; charset="US-ASCII"; delsp=yes; format=flowed
>If you want a "daily rider" that you will not have to worry about but
>that will handle well and be comfy all day, I'd suggest a Peugeot
>PX-10. They are commonly available, and can be ridden "as is" or
>modified to suit your taste (and inventory) in componentry, as they
>were often modified/upgraded with non-OEM parts, wheels, etc.
>TREKS are nice, too, but the PXs (or similar Motobecanes, Gitanes,
>etc.,) will feel more "lively" or "limber" and perhaps be more
>"forgiving" on all-day rides.
Opinions wanted! I have been converted from a off topic bike to a 1978 Trek TX700. I have discovered that I enjoy "limber" frame. How do others feel the above bikes compare to a 1970s Trek? If you feel that they have m ore flex - do you have opinion why this is the case?
Fort Worth, TX