Re: [CR] Brakes and flex

(Example: Framebuilding:Tubing:Falck)

Date: Wed, 5 Jan 2011 04:15:41 +0000 (UTC)
From: <joeb-z@comcast.net>
To: Ken Freeman <kenfreeman096@gmail.com>
In-Reply-To: <AANLkTikoANqkBfYiST2cQRNmZuWUeEXvOtX+1DjPvza=@mail.gmail.com>
Cc: classicrendezvous@bikelist.org, Charles Nighbor <cnighbor1@comcast.net>
Subject: Re: [CR] Brakes and flex


All other things being equal skidding a front wheel is an indicator of a good brake. So at that point tire adhesion is the limit of stopping power. I have only done it with Cantis. And Mathauser pads.

Joe Bender-Zanoni
Whitneyville, CT


----- Original Message -----
From: Ken Freeman
To: Harry Travis
Cc: classicrendezvous@bikelist.org, Charles Nighbor
Sent: Tuesday, January 4, 2011 9:06:51 PM
Subject: Re: [CR] Brakes and flex


Similarly, I don't think I've ever seen a measurement of "stopping power."

On Tue, Jan 4, 2011 at 3:53 PM, Harry Travis <travis.harry@gmail.com> wrote:
> Engineer Jobst Brandt has written in rec.tech and maybe elsewhere about,
> iirc, "cosine error" characteristic of all double pivot brakes, and still
> uses, seriously, as in Alpine tours, single pivot Campag Record or Super
> Record.
>
> My uninformed belief is that we've never seen measurements or images
> clearly
> pointing to where the "give" is in the bicycle braking system, so it is
> mostly attributed to the wrong parts.
>
> Please someone, show me that new design stainless steel cables stretch less
> than old-skool zinc-plated ones (any more than bicycle chains "stretch.")
> Which is to say: Show me that they measurably stretch at all, as against
> simply having the ends bed and the housings move.
>
> Or, maybe I have it completely wrong, and the greater adhesion of
> contemporary brake pads puts previously rare loads on contemporary brake
> calipers. And maybe Thor Hushovd squeezes brake levers with as much
> astonishing peak load as he sprints with and there are many more his equal
> riding as punters.
>
> Harry Travis
> Pine Barrens of NJ
> USA
>
> On Tue, Jan 4, 2011 at 7:27 PM, Charles Nighbor <cnighbor1@comcast.net
> >wrote:
>
> > I use Campanolo Record 70's and early 80's, 1st generation brakes and
> > notice no brake flex when slowing down fast coming down Mt. Diablo at 30
> > mph. Some of the older Mafac and Universal I did notice brake flex. Since
> > discarded. Modern brakes like Dura-Ace and Campagnolo Record have gotten
> > stronger looking in appearance but if I didn't notice and flex in on
> period
> > brakes why the big change in brake design. And I wouldn't mention those
> CADD
> > machined brakes.
> > Is it that in racing you need every bit of stopping power you can get
> with
> > no flex. Or is just an evolution in bicycle components.
> >
> > Thanks
> > Charles Nighbor Architect
> > Walnut Creek, CA USA
> > _______________________________________________
> >
> >
>
>
> --
> Harry Travis
> _______________________________________________
>

--
Ken Freeman
Ann Arbor, MI USA