Canti Brakes

[John B.]

I'm using cantilever brakes and I notice that the position of the
brake cable "saddle", or "cable carrier" connecting to the straddle
cable between the brake arms is rather critical in lateral position to
avoid pulling more on one side than the other.

I'm using simple curved carriers, probably Dia-Compe from the
looks,which have considerable friction against the straddle cable and
slide sideways only grudgingly and are easy to get off center with
resulting uneven brake movement.

I've seen some small "carriers" which are basically only a cable
clamp for the brake cable and a small pulley to ride on the straddle
cable that would seem to be self centering.

see
http://store.velo-orange.com/index.php/components/brakes/parts/grand-cru-constructeur-straddle-wire-roller-hangers.html
for an example.

Has anyone tried anything like this; did it work?
--
Cheers,

John B.

[Frank Krygowski]

On 3/14/2014 7:23 AM, John B. wrote:
>
> see
> http://store.velo-orange.com/index.php/components/brakes/parts/grand-cru-constructeur-straddle-wire-roller-hangers.html
> for an example.
>
> Has anyone tried anything like this; did it work?

I've got older ones, with plastic pulleys. No, they don't work very
well. They might if the straddle cable were perfectly limp, but it's
not; it's stiff.

My solution is to pre-bend the straddle cable. I bend the center of the
cable so it conforms to the curve in the hanger or saddle, and so the
cable run from the hanger to each canti arm is a straight line. This
keeps the hanger where I want it. This also reduces the flex in the
system as the brakes are being applied. No lever travel is wasted in
straightening a curved straddle cable.

--
- Frank Krygowski

[howar...@gmail.com]

Save grief by using Tektro Z link wires. Cambria Bike has them in all available lengths.
http://www.cambriabike.com/shopexd.asp#options_list
Google z link wire to find other mail order shops who have them.
Mr S.Brown liked them.
http://sheldonbrown.com/canti-trad.html
Sheldon had a discussion elsewhere on his site about canti geometry which might help in deciding which length of z link is appropriate for you.
The beauty of z link is that once you have set length of brake wire from from button to left hand canti arm, it stays adjusted by brake wire being trapped in button. Straddle wires want to describe an arc leading to wasted motion in initially pulling curve out of wire. Franks pre-bending can help but the z wire setup avoids the problem altogether. Or do what I did and abandon cantis in favour of V brakes.
PH

[Sir Ridesalot]

By raising or lowering the straddle cable you can really fine tune the feel of cantilever brakes. I also use an L-shaped gurad on any canti bike that doesn't have fenderss. That's just in case a brake cable breaks and the straddle cable drops. Without fenders or a guard that straddle cable can catch the tire and bring the wheel to a very sudden stop.

Cheers

[spincircles]

One of the best write ups I've seen on the topic is below. It's from an old collection of Keith Bontrager articles that he uysed to post as "Keith's Rants" or something like that. See below


http://web.archive.org/web/20001004190214/www.bontrager.com/rants/rant_0008_08_01_1998.html

[spincircles]

I should further note that the link to Keith's rant on canti brakes, below, has links embedded within each page. To get the full series of articles on this subject, you have to keep looking for the links and clicking to further in. Kind of a clumsy layout, but I'm just glad this info is still on the web. I use Cantilevers almost exclusively.

http://web.archive.org/web/20001004190214/www.bontrager.com/rants/rant_0008_08_01_1998.html

Spincirlces

[Sir Ridesalot]

Very interesting articles. Too bad the images and spreadsheets are gone. I liked how he said if magazines could get the spin correct then they'd be able to promote disc brakes as the needed brake type. Consider what's happened since 1999 when that article was written and see that he was prophetic.

I never knew that V-brakes were originaly developed as a means of getting brakes onto full-suspension bikes.

He really likes his cantilevers. So do I.

Cheers

[spincircles]

I agree, too bad the pics are gone. In the original pics, they detailed a wide-stance cable holder that made it easier to drop the straddle cable really close to the tire. Here is a modern version of those wide-stance cable holders.

http://americancycleandfitness.com/product/problem-solvers-wide-cable-carrier-182481-1.htm?variations=810915&gclid=CKmWmKaGmL0CFcg7MgodbA4AQg

In a nutshell, Keith ends up suggesting:
"You don't have to get weird about the spreadsheets - we're not all Dilberts. The set up basics for any cantilever brake system:

*Spread the arms at the top. Extend the pads out of the arms to do this. It seems weird, but it's important. Don't get carried away and extend them out so far that they are not held properly. Make sure they are held very tight when you are done with toe in adjustments.

*Bring the straddle carrier down as low as you can. If you don't know how close you can get to the tire, adjust the lowest point of the straddle carrier even with the underside of the fork brace. This is a clearance you use all the time and is a good landmark to shoot for.

*Adjust the pads first, then the carrier, them pull the straddle cable across and make the final cable adjustments...."

[spincircles]

The Pro to this setup, with low straddle wire and wide canti stance is high leverage with more travel than V brakes. When the rim is a little warped the pads on this setup will not rub as badly as V brake pads, which have very low travel.

The con to such a canti setup is that the break pads "dive" into the rim from higher above than when the cantis are not set up as wide. This dives makes brake pad angle critical and can result in very worn pads "diving" past the rim and into the spokes. You gotta really watch this setup, but it gives great leverage alsong with decent pad clearance.

Spincircles

[John B.]

On Sun, 16 Mar 2014 14:24:00 -0700 (PDT), spincircles
<ispinc...@hotmail.com> wrote:

>One of the best write ups I've seen on the topic is below. It's from an old collection of Keith Bontrager articles that he uysed to post as "Keith's Rants" or something like that. See below
>
>
>http://web.archive.org/web/20001004190214/www.bontrager.com/rants/rant_0008_08_01_1998.html
>>
>> Has anyone tried anything like this; did it work?

A lovely article. Of course it didn't answer, or even attempt to
answer, my question, but what the heck.
--
Cheers,

John B.

[spincircles]

The wide stance carriers that Keith was endorsing usually have set screws that allow them to be tightened down exactly where you want them on the straddle wire. The Diacompe type cable carriers usually just have no such set screw for left/right adjustment on the straddle wire.

I recall that little detail being in there, but it might have been in one of the diagrams that is now missing.

Spincircles

On Sunday, March 16, 2014 7:50:33 PM UTC-4, John B. wrote:
> On Sun, 16 Mar 2014 14:24:00 -0700 (PDT), spincircles
>

>
>
>

[John B.]

Frank, thanks for the e-mail when you had google problems but why not
use a proper Usenet reader. You can get a free copy of Forte Agent,
probably the best one, to try it.

It does make a difference, in fact I can't even begin to contemplate
reading google Usenet groups without it :-)
--
Cheers,

John B.

[spincircles]

Try these. As I noted above, they have set screws to set down on the straddle wire at the perfect left/right position. This site says that are for a road/MTB component mix adjustment, but they are also good for using with stock canti lever & brakesets that get setup with the low wire/wide arm position Keith Bontrager was ranting about.

http://www.bikeparts.com/search_results.asp?id=BPC111330&gclid=CNjrwvepmL0CFa9cMgodDHoAQg

Spincircles

[spincircles]

...and there is the little cantilever spring tension adjustment on the brake arm itself. Allows you to find-tune the amount of spring tension that each brake arm applies.

If your fork's brake stud has multiple spring post holes, that is one more, even rougher adjustment that comes even before using that set screw on the brake arm. Only once or twice, though, did I ever have brakes that were so our of balance that I did not use same, mirror set up of brake stud spring post hole.

Spincircles.

[Sir Ridesalot]

In other words you need to periodically inspect your equipment for defects.

Cheers

[Frank Krygowski]

Don't forget this article by Sheldon:

http://www.sheldonbrown.com/canti-trad.html


--
- Frank Krygowski

[Frank Krygowski]

On 3/16/2014 8:29 PM, John B. wrote:
>
>
> Frank, thanks for the e-mail when you had google problems but why not
> use a proper Usenet reader. You can get a free copy of Forte Agent,
> probably the best one, to try it.
>
> It does make a difference, in fact I can't even begin to contemplate
> reading google Usenet groups without it :-)

Google Groups has been refusing to accept posts, so I went back to
Eternal September and Thunderbird.

One definite advantage of Google Groups is, no setup required. I find
setting up E-S to be a major pain. So does the good friend I have, the
Linux geek who once told me "I was so sick with the flu, I didn't have
energy to do anything but build another computer."

I'm not looking forward to going through that setup process with three
computers, different operating systems, different networks.

--
- Frank Krygowski

[John B.]

What is E-S?

As for "setup" with Agent you need to (1) type in the provider, in my
case "news.albasani.net", enter the password and than (2) select the
groups one wants to read. Hardly an insurmountable task :-)
--
Cheers,

John B.

[John B.]

Aside from top posting you are still missing the mark. I asked a
specific question "Has anyone tried anything like this; did it work?"
and so far you don't seem be able to answer it.
--
Cheers,

John B.

[Duane]

I guess he means Eternal September. You'd do the same with Agent. You
would have to get access to Eternal September first. Pretty straight
forward. Go to their site and fill out the form. Then follow your two
steps using news.eternal-september.org for step one.

There's something a little strange with some versions of Thunderbird
though where it doesn't give you public access. You end up with just a
few groups, but this must be a known problem because one of the groups
that you end up with is the help group and it has an entry telling you
what to do when you don't see all of the groups.

[Frank Krygowski]

Yes, that was one hangup. I remembered that from previously installing
Eternal September. I think it was resolved by checking "ask for
authentication when connecting" or something similar.

Two more details that stymied me were these: For Eternal September via
Thunderbird, it was critical to set "Connection Security" to "None."

And, with this brand new Windows 8.1, I'm finding that almost any
software I install (including Thunderbird) lands without permission to
write to the hard drive! I don't know if that's due to the McAfee that
came with the machine, or if it's a default part of 8.1. But with
Thunderbird (as well as several other things I've installed) it was
necessary to dive down to the *.exe file and give it specific permission
to write to disk, etc.

Maybe it's Win 8.1's version of friction paste?

--
- Frank Krygowski

[John B.]

On Mon, 17 Mar 2014 12:00:01 -0400, Frank Krygowski

There is an old British phrase that would seem to apply - "Horses for
courses", or in other words, don't enter a plow horse in the Grand
National and don't buy a race horse to pull a plow.

Thunderbird is a good e-mail program.
--
Cheers,

John B.