Re: AW: [CR]Woman's frame (not mixte) lightweights?


Example: Framebuilders:Masi

From: freesound@comcast.net
To: "Schmid" <schmidi@gaponline.de>, "'Jerome & Elizabeth Moos'" <jerrymoos@sbcglobal.net>, "'Mark Stonich'" <mark@bikesmithdesign.com>, <classicrendezvous@bikelist.org>
Subject: Re: AW: [CR]Woman's frame (not mixte) lightweights?
Date: Fri, 06 Jul 2007 16:50:36 +0000


Mixtes with twin lateral tubes running from the headtube to teh chainstays, only tied to the sides of the seat tube, suffer from less torsional (pedaling and turnign) rigidity than diamond frames, or frames with a single dropped top tube brazed to the seat tube. The added resistance of a second full diameter tube, whether it is level or not, seems to be fairly important. The attachment of a seatstay at the seat lug, without the presence of a top tube in compression, should (it seems to me) result in vertical bump loads causing the seat tube to flex, and possibly allowing the rear wheel to go out of plane relative to the BB and head tube. Sounds like good news for a cushy ride, but bad news for aggressive handling or load carrying.

Ken Freeman
Ann Arbor, MI USA


-------------- Original message --------------
From: "Schmid"

> I recently sold some womens frames since nobody around me wanted to ride

\r?\n> the complete bikes. So I decided to part them out. In measuring i found

\r?\n> out that they are relatively long. As an example a 51 frame had a 57cm

\r?\n> toptube-length. My conclusion was that they made the seat tube shorter

\r?\n> for use of a longer seatpost in order to obtain a shorter and therefore

\r?\n> stiffer rear triangle to compensate for the loss of stiffness due to the

\r?\n> lowered toptube. I might be wrong here since I am not a geometry expert.

\r?\n> My girlfriends always prefers mens frames for better handling qualities

\r?\n> and a stiffer ride. Whenever I tried to ride a womens bike it felt

\r?\n> sloopy and not stable. I think it does not make sense to alter the well

\r?\n> constructed mens diamond frame setup in a race bike just to make it

\r?\n> easier to mount the bike without having to lift your leg over the

\r?\n> saddle. It makes some sense in city or touring bikes when women ride

\r?\n> with a skirt but I have never seen a woman ride a race bike with a

\r?\n> skirt. My impression is also that those bikes were mostly bought by men

\r?\n> for ther wives in order to get them into riding but then those bikes are

\r?\n> never ridden. All women I know who ride seriously ride mens frames.....

\r?\n>

\r?\n>

\r?\n> Michael Schmid

\r?\n> Oberammergau

\r?\n> Germany

\r?\n> Tel.: +49 8821 798790

\r?\n> Fax.:+49 8821 798791

\r?\n> mail: schmid@zunterer.com

\r?\n> http://www.zunterer.com

\r?\n>

\r?\n>

\r?\n> -----Urspr√ľngliche Nachricht-----

\r?\n> Von: classicrendezvous-bounces@bikelist.org

\r?\n> [mailto:classicrendezvous-bounces@bikelist.org] Im Auftrag von Jerome &

\r?\n> Elizabeth Moos

\r?\n> Gesendet: Donnerstag, 5. Juli 2007 19:04

\r?\n> An: Mark Stonich; classicrendezvous@bikelist.org

\r?\n> Betreff: Re: [CR]Woman's frame (not mixte) lightweights?

\r?\n>

\r?\n>

\r?\n> I've thought about picking up a women's Paramount for my wife if I find

\r?\n> a bargain. One thing I've noticed on those on eBay. The headtubes seem

\r?\n> to be very long compared to the seatube, which would place the bars high

\r?\n> for a "normal" amount of exposed seatpost. That is, it seems that if

\r?\n> there were a toptube connecting the seatlug and headlug, it would slope

\r?\n> noticeably upward from seatlug to headlug. I suppose this might have

\r?\n> been done to raise the bars as Rivendell much more recently has

\r?\n> advocated. Was there some other reason for this design feature? Did

\r?\n> other makers of this type of frame do the same?

\r?\n>

\r?\n> Regards,

\r?\n>

\r?\n> Jerry Moos

\r?\n> Big Spring, TX

\r?\n>

\r?\n>

\r?\n> Mark Stonich wrote:

\r?\n> Does anyone have experience with "Woman's" frame (not mixte)

\r?\n> lightweights? They get no respect, but builders not known for

\r?\n> putting out floppy frames, such as Grandis

\r?\n> http://www.bikecult.com/works/archive/06bicycles/grandisEXrs.JPG

\r?\n> Schwinn Paramount P65

\r?\n> http://www.geocities.com/sldbxtralite/1974/74xlite06b.jpg

\r?\n> or Colnago.

\r?\n> http://www.hollywoodsgarage.ca/images/body/large/showbikes.jpg

\r?\n> have used this design.

\r?\n>

\r?\n> BTW I'd love to see links to others

\r?\n>

\r?\n> I'm wondering if they performed significantly differently than the

\r?\n> men's versions of similar bikes.

\r?\n>

\r?\n> I also would like to know what size seat posts they used. (To

\r?\n> estimate seat tube wall thickness.)

\r?\n>

\r?\n> I'm thinking about building my wife a lighter frame.

\r?\n>

\r?\n> I could build her another, lighter, mixte. But the article by Peter

\r?\n> Weigle in this month's Bicycle Quarterly has me thinking about the

\r?\n> relative merits of the Woman's frame vs. the Mixte. Most of the added

\r?\n> rigidity of a Mixte over a "Womans" frame seems to be in the vertical

\r?\n> plane.

\r?\n>

\r?\n> One of the challenges of building a good frame is reducing vertical

\r?\n> stiffness (within limits) without sacrificing torsional rigidity. A

\r?\n> high quality seat tube can give significant vertical compliance

\r?\n> without ever nearing it's yield point. I'm wondering if it might be

\r?\n> better to invest the weight of the mixte stays in slightly heavier

\r?\n> seat tube and chainstays.

\r?\n>

\r?\n> This bike would be used for day trips or supported touring by a rider

\r?\n> who probably weighs about 180 lbs and who never stands when riding.

\r?\n>

\r?\n> Mark Stonich;

\r?\n> BikeSmith Design & Fabrication

\r?\n> 5349 Elliot Ave S. - Minneapolis. MN 55417

\r?\n> Ph. (612) 824-2372 http://bikesmithdesign.com

\r?\n> http://mnhpva.org