Canti Brake setup suggestions...

[konstantkarma]

I am using a set of Paul Touring on the rear, and Neo Retro Cantis on the front of my new to me cross bike. After not using cantis for so many years I remembered how bad they really are. The front brake works fairly well, but the rear might as well not even be there. I spent a fair amount of time setting them up and got them toed and aligned with the rim, but nada. Riding off road is really interesting when you have only a front brake to slow you down.

Am I missing something? Is there a reasonable way to make these brakes, oh, I don't know, actually slow the freakin' bike? :crap: Are cantis outdated technology, only hanging around because of mud clearance?

Your tips are appreciated.

[bfd]

You have some of the best canti brakes on the market! Assuming your brakes are properly set up, I would try replacing the pads with Kool Stop Salmon colored brakes pads like the Eagle 2 here:

http://www.koolstop.com/brakes/index.php#Anchor-adjustments-61748

If that doesn't work, look towards something like mini-v brakes. Good Luck!

[RPS]

A picture of the yoke angle would be helpful since it's so critical. A good source of information from the late Sheldon Brown.

http://www.sheldonbrown.com/cantilever-geometry.html

[palincss]

You have some of the best canti brakes on the market! Assuming your brakes are properly set up, I would try replacing the pads with Kool Stop Salmon colored brakes pads like the Eagle 2 here:

http://www.koolstop.com/brakes/index.php#Anchor-adjustments-61748


Salmon Kool Stops are always a good idea. However, there's no way konstantkarma's brakes could possibly be properly set up: as you say, those are some of the best canti brakes on the market. If it were me I'd take the bike to a good bike shop and have them set the brakes up.

[bgcycles]

I am using a set of Paul Touring on the rear, and Neo Retro Cantis on the front of my new to me cross bike. After not using cantis for so many years I remembered how bad they really are. The front brake works fairly well, but the rear might as well not even be there. I spent a fair amount of time setting them up and got them toed and aligned with the rim, but nada. Riding off road is really interesting when you have only a front brake to slow you down.

Am I missing something? Is there a reasonable way to make these brakes, oh, I don't know, actually slow the freakin' bike? :crap: Are cantis outdated technology, only hanging around because of mud clearance?

Your tips are appreciated.

Most of the problems setting up cantilevers is cable drag and the old style straddle wire and cable carrier.

First try replacing the old straddle cable with a "Linkwire" - they give a much more positive feel and come on right away.

The old straddle cable takes lever movement to take up the slack.
Check out the Linkwire setup at - http://www.bgcycles.com/accessories.html - about half way down the page.
Regards,
Bruce Gordon

[shiftyfixedgear]

Worth keeping in mind is that rear brakes don't do that much to begin with, but they should offer some stopping / feathering ability. Check that your rims and pads are clean and free of any oil residue. This is one reason that rear brakes can be so inneffective. Lightly scuff the rim with sandpaper AFTER you wipe it off with denatured alcohol or acetone. This time of year there is lots of crap on the roads and it is also easy for the rims to pick up oil that is washed off the chain and cassette. This is true of all brakes - not just weak cantis.

Second - go to Saint Sheldon Brown's website and go through what he says about set-up and straddle cable heights. Check that you have the cable free from flex and friction as best as possible.

Thirdly - low-profile cantis IMHO are trickier to set-up where you find the "sweet spot" of good lever "feel" and effective braking power. The neo-retro type high straddle cable design never gave me as much of a challenge as the low-profile ones. The engineering types can argue all day that with a careful set-up there should be the same mechanical advantage / leverage/ whatever, but I think there is just more of an "acceptable" range of set-up on those wider older style of canti.

If you cant make the cantis fly then the Tektro mini-vees seem to be getting good reviews.

[thwart]

Saint Sheldon Brown Time to start an email campaign:

benedictXVI@si-dapopeiscatholic.org

And who could be more deserving?

[RPS]

....snipped....
Thirdly - low-profile cantis IMHO are trickier to set-up where you find the "sweet spot" of good lever "feel" and effective braking power. The neo-retro type high straddle cable design never gave me as much of a challenge as the low-profile ones. The engineering types can argue all day that with a careful set-up there should be the same mechanical advantage / leverage/ whatever, but I think there is just more of an "acceptable" range of set-up on those wider older style of canti.
....snipped.....
It’s not just your perception in my opinion, there is indeed a wider range of acceptable setup because at the extreme when the arms stick straight out the brakes’ function is essentially linear just like that of a V-Brake (different mechanical advantage but operation of both is near linear). On the other hand the more upright the arms (low profile) the less linear it becomes and the more it can be affected by setup. Improperly set up a low profile cantilever brake like the one in the OP can have very low mechanical advantage and therefore not be able to stop a bike very well.

As an engineer I could argue that if properly set up a low profile canti can do an OK job but I won’t because I don’t like them. Although of a different brand than the OP’s I got rid of mine on a tandem and would never use them again – they just couldn’t stop the bike adequately. Just my personal taste – I like things simple and predictable, and I don’t want to spend time adjusting brakes because the pads wear down a little and that in turn affects the mechanical advantage, etc….

If I needed heel and fender clearance maybe I’d accept the added inconvenience of these touring brakes, but eliminate either need and I’d prefer other options.

[konstantkarma]

So, Link wire and Kool Stop Salmon should do it? I will give this a try. Thanks for your suggestions!

[Frankwurst]

I have this same setup on more than one bike. It's not the brakes. Try what the others have recommended and I bet you'll like the results. :beer:

[konstantkarma]

So the rear brakes are shod in Kool Stop black and the setup is shown below.

I also increased the tension on one brake side (a very easy and nice feature of Paul pedals is a tensioning nut for each caliper) which was not pulling back as well as the other. It also looks like I toed in one side on too steep an angle. So I re-set this. Thanks for the feedback!

[DRZRM]

I'm no Guru of canti's like some other here are, but your straddle cable looks too high, seems like you need to drop your yolk for increased mechanical advantage.

[Benjamin]

i agree that the yoke looks a bit high for this particular setup, but not too crazy.

also, check that you're not using excess cable housing and don't have any funny bends, especially in the bit running around the seatpost.

what was already said regarding rear cantis, they don't really do a whole hell of a lot. on road bikes, it's said the braking power is distributed 70/30 front/rear. on canti mountain/cross bikes, i feel it's more like 85/15.

consider switching to a set of TRP CP-9 mini-V brakes!

[RPS]

So the rear brakes are shod in Kool Stop black and the setup is shown below.

Are you sure you are not bottoming out the yoke against the frame? Looks very close if you took the picture without the brake being applied. It's hard for me to tell from a picture, but the pad looks like it's off the rim, in which case the yoke may not be able to travel up enough for you to get full brake application. If that's the case you can pull on the lever all you want and the brake won't do anything more.

[John M]

I agree that the straddle cable hanger is a bit too high. When the brake is engaged, you want about a 90-degree angle between the cable and the brake arm. I have those same Paul brakes, and find that the rear gives enough power to easily lock the rear wheel when set up right. Also, not as much toe is needed on the rear compared to the front.

[veloduffer]

I've used cantis for years, including Paul's and they are generally a pain to set up correctly. However, I recently installed a set of Cane Creek SCX-5 cantilevers on a cross bike- super easy with the link wire (like Shimano, so the angle is set) and it has a micro adjuster to adjust the distance between the rim and pads evenly. $39/pair direct from Cane Creek. :hello: :banana:

[RPS]

No brake will work if brake cable travel is limited.

IMO when a brake doesn’t work at all as stated in the OP it has to involve more than a little misalignment, too little mechanical advantage, toe being off a little, etc…. Those things can diminish performance but it doesn’t make a brake completely inoperative.

The most likely explanation is that the brake is not being applied; or not being applied enough.

Road brake levers typically pull about ½ inch of cable and I’d bet that can’t happen here before the yoke hits the frame first. If my guess (based on posted pictures) is correct making other adjustments won't solve the problem. For safety reasons there should be at least an inch clear above the yoke to make sure brake cable travel isn’t limited.

Lowering the yoke will also improve mechanical advantage, but that's a different issue -- and one not quite as critical IMO.

[konstantkarma]

No brake will work if brake cable travel is limited.

IMO when a brake doesn’t work at all as stated in the OP it has to involve more than a little misalignment, too little mechanical advantage, toe being off a little, etc…. Those things can diminish performance but it doesn’t make a brake completely inoperative.

The most likely explanation is that the brake is not being applied; or not being applied enough.

Road brake levers typically pull about ½ inch of cable and I’d bet that can’t happen here before the yoke hits the frame first. If my guess (based on posted pictures) is correct making other adjustments won't solve the problem. For safety reasons there should be at least an inch clear above the yoke to make sure brake cable travel isn’t limited.

Lowering the yoke will also improve mechanical advantage, but that's a different issue -- and one not quite as critical IMO.

Thanks for your input. The yoke does not hit the cable hangar at full compression of the lever (it appears closer to the hangar in the photo than it actually is).....so that's not the reason braking is poor. Also, you can see in the photos where I shortened the spanner cable on the left caliper. The length of this cable was set to allow enough clearance to disengage the brakes to remove the wheel. However, I will see if I can shorten it any further and try to move the yoke closer to the span cable.