RE: [CR]The definitive frame sizing........

(Example: Production Builders:Peugeot:PX-10LE)

To: classicrendezvous@bikelist.org
From: "Ken Wehrenberg" <wnwires@htc.net>
Subject: RE: [CR]The definitive frame sizing........
Date: Sat, 16 Jul 2005 10:53:17 -0500


List:

I was FitKitted in the mid '80s at Phoenix Cycles in Carbondale, IL. I rode with that position for quite some time. It really was a different position for me as at that time, (I think the system has been modified some since) it gave riders a saddle height that was most likely quite a bit lower than what they had been accustomed to.

However, from a comfort and efficient riding position standpoint, I now feel there is a "third rail" which I will touch briefly on: bike handling. Just like a sportscar, it is a worthwhile goal to attempt to attain a 50-50 weight distribution front to rear. For each body weight type, this attempt to equalize can mean drastic geometry alterations. It can, for lighter climber sorts such as I am, mean shoe overlapping the front wheel, which must be brought back under the rider more. Finally all this was put together for me when I was fitted by the Seven Cycles system. I received rather drastically forward body position relative to the front wheel, but the noticeably improved handling was something the likes of which I never experienced. One more thing: Stem length. It takes around an 11cm or so to achieve this in order to move the weight forward enough.

In regard to height of stem versus saddle, I will opine that the pics we probably all have seen of higher stems a la Rivendell show pronounced flexion in the lumbar areas of the lower back. The resulting compression on the anterior portion of the vertebrae and the corresponding posterior extension make me think "ouch" whenever I see that out on the road. The key to avoid this is to be able to flex the pelvis downward and forward. When one does this, the back stays flat and the bars can be comfortably positioned around 2" below the saddle. However, (and this is a big however) most people I know, as we get older, find that the ability to flex the pelvis downward can be severely curtailed by the usage of Brooks and Ideale saddles. They can get pretty uncomfortable. It's why I now like to use Selle Italia's holed saddles even on my vintage riders. BTW, the red one is a stunning match for the LeJeune and makes it a wonderful all day rider even if it isn't period correct.

Ken Wehrenberg, Hermann, MO