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Old 11-15-10, 12:48 PM   #1
corkscrew
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Two specialized city bikes (Hard rock & Rockhopper) canti-lever issues.

So I've recently brought these two frames back from the dead (both found @ the scrap yard in various states, and brought back to life with my parts bins and help from the local bike coop).

First - the rockhopper.




This is mine. The pads are kool stop Eagle 2 dual compounds. The pads are pulled from my T700 touring bike, so probably have a few hundred miles on them.

The setup works VERY well. The bike stops dead with the levers at half travel.

Meanwhile - the hard rock, I've built this up for a friend, to be her school commuter. (She currently walks 2 hours a day to get to campus).





It stops. But not nearly as well as the rockhopper. It has new Salmon Koolstop Eagle II pads.


The only thing I can think of is the little "wedge" at the end of the Eagle II pad is more worn down on the rockhopper, enabling more pad contact. Otherwise they are both using old dia-compe road levers, new cables & housings etc.

Any ideas?
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Old 11-15-10, 01:05 PM   #2
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On the orange bike, move the levers up the handlebars a bit. They're too low. The upper lever (aka suicide lever, aka safety lever) will reach the top of the bar before you've fully engaged the brake.
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Old 11-15-10, 03:04 PM   #3
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The lever height on the red bike (orange in the photo) was set by the girl who is riding it. It needed to be that low for her to reach the brakes in the drops. She can still reach the "saftey" lever. Would that really affect canti-lever braking performance?
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Old 11-15-10, 03:07 PM   #4
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I don't know if your problem is primarily or fully caused by the lever placement, but I do know that you should fix it. If she needs help reaching the lever on the drops, just rotate the bar down (forwards) a bit. The safety lever is much too close to the bar and is rendered ineffective!
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Old 11-15-10, 04:30 PM   #5
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Idk if that suicide-lever set-up works with canti's, but--
you could let out the canti arms as far as the yoke cable will allow (resulting in using more of the brake-pad's post length). That may increase the canti's force.

I'm shovin' around a flat-bar '93 Rockhopper atm, and I have its canti's set as wide as they'll go. They work.

Sheldon explains here.
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Old 11-15-10, 04:41 PM   #6
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Well that's the perplexing thing. I don't have the studs out all the way. Both bikes have the canti's with about two of the lines sticking out from the brake arm. It works just fine on the rockhopper?

I'll try that on the Hard rock tonight. I'll see what I can do about the suicide levers. (I kept them around thinking they'd go on someone elses bike anyway, i can't stand the way they look).

I thought most road levers (with the exception of the long-pull variety) were compatible with canti's?
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Old 11-16-10, 12:49 AM   #7
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The braking sucks on the orange bike because the brake pads are mounted too close to the brake arms. Take a look at the straddle cable when you pull the brake lever, I bet it ends up at an extreme angle (somewhat close to vertical). This gives you almost no leverage. You have to redo the pad's position, putting them farther away from the brake arms. You want the straddle cable to have roughly a 45 degree angle or less. Here's a better way to visualize it:
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Old 11-16-10, 06:24 AM   #8
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The braking sucks on the orange bike because the brake pads are mounted too close to the brake arms. Take a look at the straddle cable when you pull the brake lever, I bet it ends up at an extreme angle (somewhat close to vertical). This gives you almost no leverage. You have to redo the pad's position, putting them farther away from the brake arms. You want the straddle cable to have roughly a 45 degree angle or less. Here's a better way to visualize it:
Depending on the rims you're using, you may want to play with the washers between the pads themselves and where they mount to the brake arms. I think that's what Reason is getting at. I had this problem back when i first started using cantilevers; my rims were too wide for the stock set-up, and i had to switch the washers to get the leverage right. Things will improve as the pads wear in, but the deficiency wouldn't be as pronounced as you describe.

hth,
-rob
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Old 11-16-10, 07:35 AM   #9
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corkscrew, It may also be that the pull ratio of the levers aren't compatible with the cantis. I have a similar issue with a road brake lever swap with a road brakeset. More lever travel and slightly less braking power. Is it unsafe for her to ride?

Brad
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Old 11-16-10, 09:55 AM   #10
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What reason said, and drew, is what the issue was with my ex wife's canti setup was. Put more of the brake pad post on the inner side of the levers. The arms should come close, but not past parallel to the rim sidewall with the brakes contacting the rim, as it stands they're going way past that, and losing all braking ability.

With low profile cantis spread em wide, keep the yolk low, and you're at a good starting point.

It's looking like that front reflector will be in the way of the straddle cable, might want to snag a handle-bar mounted one instead.

Those safety levers should come no-where near the bars when the brakes are applied, that's bad news. Rotate the handlebars or bring up the levers, but don't leave it like that. If she has small hands, get WSD levers, with cross (interrupt) levers for the tops. Should run around $50 bucks.

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Old 11-16-10, 10:53 AM   #11
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The saftey levers don't touch the bars when the brakes are applied.

I guess I'm missing the point.

I'll still move them up when I get a chance to play with it tonight. I'll be sure to give plenty of test rides myself before I hand it over to her. (It stops the bike on the stand, need to try it on the ground.).

I'll also play with the canti pads. Although these are straight posts, not washer/bolt designs.

Worst case scenario I'll pick up a different set of brake levers @ the coop this weekend. (Only put saftey levers on because they were in my parts bin, and I won't put them on a keeper).
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Old 11-16-10, 11:15 AM   #12
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The folks who are suggesting you want the yoke cable to brake arm angle to be about 90 degrees when the pads meet the rims are dead on.
10 lbs of force at 90 degrees is 10 lbs of force applied the direction you want
At 180 degrees-pulling straight up- 10 lbs of force is 0 lbs applied
At 45 degrees 10 lbs is just 7 lbs in the direction you want (if my trig is correct)

Usually you can get away with lever with the wrong mechanical advantage if that is what is happening here. It isn't ideal of course-too much mechanical advantage is safer than too little as long as you have enough lever travel-too little mechanical advantage would be more of a problem for a smaller person/older person-less than ideal.
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Old 11-16-10, 01:31 PM   #13
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If you want corkscrew i cant take a pic on my bike to see what they're talking about, i had the same issues with mine, i run touring canti's which are a little different but same concept. Make the straddle wire a little longer, than move the pads them selves towards the rims, to get the actual canti arms away from the rim, than after that start messing with the yoke height. Im still having a hell of a time getting it just right on my kuwie but i blame that on the next to no travel STI's i have.
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Old 11-16-10, 01:33 PM   #14
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Also the one guy, i never remember his name, the one that wears the coverall at BBP and rides the extra cycle, i think he's the one that a wiz with canti's
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Old 11-16-10, 01:54 PM   #15
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Cantilever brakes do take a long time to set up well.
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Old 11-16-10, 02:04 PM   #16
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Cantilever brakes do take a long time to set up well.
When you finally do get em right though, IMO best brakes out there
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Old 11-16-10, 02:20 PM   #17
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Also the one guy, i never remember his name, the one that wears the coverall at BBP and rides the extra cycle, i think he's the one that a wiz with canti's
I'll keep that in mind. I'm not sure who rode that xtracycle, but I'll keep my eyes open. I'll probably be down there Saturday for parts anyway if these brake levers don't agree with me tonight.
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Old 11-16-10, 02:46 PM   #18
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When you finally do get em right though, IMO best brakes out there
Each has advantages, but yes, I like them quite a lot. A couple of years ago, I built up a Surly Cross Check from the frame only. I could have put V brakes on, but I chose cantilever. I don't regret it at all. I got the low-end Shimano ones and am even using the original pads. I'm very happy.

Sidepulls (with a single pivot) are the easiest to adjust, and you don't have to move the shoes up or down as they wear. With all others, you do.
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Old 11-16-10, 02:54 PM   #19
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I'll keep that in mind. I'm not sure who rode that xtracycle, but I'll keep my eyes open. I'll probably be down there Saturday for parts anyway if these brake levers don't agree with me tonight.
They have a pair of shimano 600 levers there for 10bucks, i was gonna get them but saw the tektro and liked em better cause they're black, i might mosey on down there sat or sun, ill make sure to ride the new giant so, if i happen to see you, you can check out the brake setup on that, they're still not the same as you have but much more sim. setup and i can endo on that thing even with loaded bags on the back
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Old 11-16-10, 03:33 PM   #20
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I like my V's - Just put Avid SD7's with kool stop mtn pads on my t700, wonderful setup! I've had good luck with canti's before. (The rockhopper stops rather quickly). Just getting frustrated with her bike, but after I took last night off I'll tackle it again.

Also - on the red bike. The front reflector bracket was placed under the straddle wire by design. Heard about the risks of a random cable brake sending the yoke wire into the wheels, and didn't want to risk it on someone else's ride. The cable carrier has about 1mm of clearance from the bracket, and I can bend it more tonight if I need to lower the cable further.


Yeah I saw those 600 levers, as well as the tektro's. I wasn't in the need for brake levers @ the time though (Got tektro long pull levers @ the Hyde park going out of business sale). Hoping to grab one of those Deore XT 9 speed RD's for my roomies Cannondale. Although most of my bike project money now will be going towards a Terratrike Tour frame. Just have to find a decent framebuilder to patch the crack.
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Old 11-16-10, 07:28 PM   #21
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I am so angry i missed hyde park cyclings going out of buisness sale, then i thought maybe they will have a booth at the hyde park street fair and well they didn't, but good luck with the brakes just take your time and dont over think it
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