Re: [CR] Brakes and flex

(Example: Framebuilders:Cecil Behringer)

Date: Tue, 04 Jan 2011 12:54:47 -0800
From: "verktyg" <verktyg@aol.com>
To: Charles Nighbor <cnighbor1@comcast.net>, Classicrendezvous@bikelist.org, Bob Freitas <freitas1@pacbell.net>
References: <1AF44DEDBB574D42885E6BF8375640B8@gateway2v8e13w>
In-Reply-To: <1AF44DEDBB574D42885E6BF8375640B8@gateway2v8e13w>
Subject: Re: [CR] Brakes and flex


Charles,

I managed a bike shop in Albuquerque, NM while I was going to school back in the 70s. We were the "pro shop" in town so I got to try out most of the new stuff that came along.

Sacrilege, hide the kids, cover your eyes...

I never liked Campagnolo brakes back in the day because from my experience, they didn't stop well! Most of it was due, in my opinion to very hard brake blocks.

The fantasy of "brake modulation" was just an excuse for justifying expensive, poor stopping brakes.

In 1975 I switched to the then new Weinmann Carrera brakes because they had superior stopping ability. That was mostly due to the brake block material. I even modified the Weinmann X-blocks to fit Campy brakes which allowed them to stop well too.

The absolute worst slowing down (can't say stopping) brake pads were the red fibrous ones used on Universal 61 and 68 brakes. They only served to polish your rims.

MAFAC brakes were flexy but always (read sometimes) stopped well... with the right brake blocks.

There were 3 different types of MAFAC blocks (not necessarily by intention): hard, soft and fibrous. The hard ones were useless for stopping and the fibrous blocks had so much fiber filler that they self destructed after very little use. The soft blocks STOPPED!

Getting back to your question about the newer brakes, the dual pivot brakes have much more stopping power than older side or center pull brakes. IMO, they rank just under cantilever brakes for stopping ability.

Not all of these dual pivot style brake have the same performance and yes rigidity does make a difference. Jan Heine did a study on this a while back.

I have a set of OT Campy Centaur dual pivot brakes on one of my KOF bikes. They have nowhere near the stopping power of the current OT Shimano 105 brakes (cheaper versions of DuraAce brakes).

I also have some earlier model Shimano 105 brakes that are less rigid. Even with the later 105 pads they don't stop quite as well but they are still better than the OT Campy Centaur dual pivot brakes.

Over the past few years, I've gathered up a number of all Campy NR/SR bikes. What I've discovered is there are drastic differences in the brake block performances on these bikes.

One of my recent acquisitions, a 1970 Gitane Super Corsa has Campy brakes from the late 70s. They have amazing stopping power, again the original Campy brake pads.

I've come to the conclusion that regardless of age, there was a lot of variance in the brake block materials that were used in classic brake blocks. This results in better or poorer stopping ability no matter what brand.

I like to feel a degree of retinal detachment when I have to lock up my brakes! ;-)

Chas. Colerich Oakland, CA USA


> 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