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  1. #1
    Senior Member agobel's Avatar
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    I guess I don't really need to stop...

    Some Craigsluck recently landed this '91 Schwinn Crosscut in the lap of yours truly. Hop below the pictures if you'd like to skip to the point. I've made some small adjustments and upgrades to the bike already. It rides like a dream, and all the parts (original and newly installed) seem to be working together like best friends, save one. When I apply the front brake at moderate to high speed, the whole front fork or wheel seems to shake. The speed and intensity of the shake increases relative to mine. This isn't intense enough to be dangerous, but something clearly isn't right. The pads look original and feel about as hard as plastic to my fingernail. Nothing appears loose, bent or mis-adjusted in the wheel, brake, fork or headset areas. Does this 20 year old bike need more than its museum fresh paint suggests, or will new pads do the trick?





    I've only ever replaced road bike pads with a universal Bell pad from a retailer I'm ashamed to admit I patronize. What's the best option for replacing these pads online for under $15 shipped for both sets? What would you pick, how are they compatible, and why are they the best? Thanks for the input and advice, and happy trails!

    Note: The reflective strap holds the wheel in place while the bike's on the stand ONLY.
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  2. #2
    Subjectively Insane MilitantPotato's Avatar
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    Check your headset, it may be loose. Also check your rim to see if it's narrower, wider, or bent in any places.

    If the pads are that old, definitely replace.

    There's many guides on google in video and text form.

    Just make sure they don't rub the tire when clamped, or released, and aren't diving bellow the rim into the spokes at all.

    If they squeal, put a business card, match box top, or small rubber-band around the rearward end of the pad to give it some "toe-in."

    To make adjusting easy, use a hairband or fairly beefy rubber band to squeeze the brake lever to your bars. That helps them hold position while ya fiddle with getting them aligned properly.
    Last edited by MilitantPotato; 03-09-11 at 02:41 AM.
    You've got a bike, so you gotta move.

  3. #3
    Senior Member Bikedued's Avatar
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    I would replace the brakes entirely, those exage pieces weren't exactly stellar when new. There are BUNCHES of new cantilever brakes on the market now, thanks to the popularity of Cyclocross. Money well spent! Grab the top of those brakes and push them back and forth
    front to back. I bet there's a LOT of play in them. No amount of toeing or new pads will stop the shake if the bushings are shot, which I woould be willing to bet they are. Definitely check the headset bearings, as mentioned already.,,,,BD

  4. #4
    Certified Bike Brat Burton's Avatar
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    The kinda behavior you`re describing really can`t be attributed to the brake pads. If the pads are glazed or hardened with old age, they lose frictional coefficient any you just don`t stop.

    What you`re describing is more likely related to play in the bearings and a rim thats not uniform in width. Before CNC machining became popular on braking surfaces that was pretty common but can also be a result of road damage.

    Easy check is simply to back out the brake adjuster on the brake lever and bring the pads on those cantilevers in to the point that they actually contact the rim. Now turn the wheel by hand. If you feel areas where the resistance varies considerably - then you have your answer.

  5. #5
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    Front brake shudder is common in bikes with the main cable threaded through the stem. This arrangement amplifies any effects of fork flex and loose headsets. Your first step should be to adjust the headset as tight as possible while still allowing free rotation. This is a bit tighter than just taking up any slack.

    Then gently apply the brakes and push the front wheel against them. If you still feel shudder, look to see if the shoes are rotating forward into a slight toe out position. If so, re-adjust the shoes with the toes in slightly so that the moving wheel rotates them flat to the rim. Long tailed brake shoes counter this rotation better, so replacing the shoes with long tailed ones will help.

    Lastly as I said, stem mounted routing amplifies shudder, so if it isn't resolved, buy a fork mounted cable hanger and re-route the cable. I suggested this last, because it's usually only necessary with light flexible forks, but it's definitely something to try.
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  6. #6
    Senior Member agobel's Avatar
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    Quote Originally Posted by MilitantPotato View Post
    Check your headset, it may be loose. Also check your rim to see if it's narrower, wider, or bent in any places.

    If the pads are that old, definitely replace.
    Thanks for the tip. I can't find play in the fork or handlebars when I'm not riding the bike. Can I use a large wrench to safely tighten the headset? Also, if I half squeeze the front brake while the bike's on the stand, and slowly turn the wheel with my other hand, the brake pads feel like they rub inconsistently around the rotation. I still can't tell what's causing the problem at this range. I don't have much experience with brake adjustments beyond tightening and loosening. I intend to replace at least the pads, but I don't know what size and shape will fit my rim.
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  7. #7
    Senior Member agobel's Avatar
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    Quote Originally Posted by Burton View Post
    What you`re describing is more likely related to play in the bearings and a rim thats not uniform in width... Now turn the wheel by hand. If you feel areas where the resistance varies considerably - then you have your answer.
    This was extremely helpful; thank you! This bike is in almost literally showroom condition. I can't imagine the rims being damaged. Are you saying this was common due to the way they were made at the time? Could any feature in a brake, lever, or replacement pad reduce the problem on this rim? Thanks again.
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  8. #8
    Senior Member agobel's Avatar
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    Quote Originally Posted by FBinNY View Post
    Front brake shudder is common in bikes with the main cable threaded through the stem... Lastly as I said, stem mounted routing amplifies shudder, so if it isn't resolved, buy a fork mounted cable hanger and re-route the cable.
    This caught my attention, too. The front brake cable housing, which indeed goes through most of the stem, was the only one I didn't replace the other night. It seemed to bend so tightly inside there, I couldn't feed a length of fresh housing through in its place. I put the old, bent housing which seemed "trained" back in, then slid the new cable through after a light dip in grease. Do you think this is my problem area? Thanks for the reply.
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  9. #9
    Senior Member agobel's Avatar
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    Quote Originally Posted by Bikedued View Post
    I would replace the brakes entirely, those exage pieces weren't exactly stellar when new. There are BUNCHES of new cantilever brakes on the market now, thanks to the popularity of Cyclocross. Money well spent! ...BD
    I did say I wanted to spend around $15 for the replacement pads, and I didn't ask if this $400 bike was top of the line in 1991. "The Exage is not the issue here, Dued!" That being said, would any full sets of eBay cantis + pads under $40 solve my braking problems forever? Thanks for your response.

  10. #10
    Certified Bike Brat Burton's Avatar
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    Quote Originally Posted by agobel View Post
    This was extremely helpful; thank you! This bike is in almost literally showroom condition. I can't imagine the rims being damaged. Are you saying this was common due to the way they were made at the time? Could any feature in a brake, lever, or replacement pad reduce the problem on this rim? Thanks again.
    I guess I can cite you a specific rim as an example. Wolber Alpina rims from the 80s were considered a pretty good rim with some fairly respectable technology: Hard anodizing, spoke holes offset and equipped with eyelets. They were standard equipment on a lot of higher end road bikes at the time. But they didn`t have machined braking surfaces.

    So directly related to the production method used to drill the spoke holes or secure the eyelets - the braking surface had subtle waves where the metal was distorted immediately next to each spoke. It was most noticable at lower speeds.

    We`re kinda spoiled today.

  11. #11
    Senior Member agobel's Avatar
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    Quote Originally Posted by Burton View Post
    It was most noticable at lower speeds.
    This makes me want to stop thinking about the brakes and get pad specific advice. The rims are 1991 Araya VX-300's, FWIW. I cleaned them thoroughly the day I got the bike. They're free of residue. The shaking, shuddering sensation, whatever you want to call it, isn't intense enough to feel unsafe, and I noticed it most maintaining a slow speed on a very steep grade. The brakes don't have much stopping power right now at high speeds, however.
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  12. #12
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    Quote Originally Posted by agobel View Post
    This caught my attention, too. The front brake cable housing, which indeed goes through most of the stem, was the only one I didn't replace the other night. It seemed to bend so tightly inside there, I couldn't feed a length of fresh housing through in its place. I put the old, bent housing which seemed "trained" back in, then slid the new cable through after a light dip in grease. Do you think this is my problem area? Thanks for the reply.
    I adhere to the theory that the primary cause is shoe rotation when the front wheel pushes the shoes forward. you can see this for yourself if you do the experiment I suggested. Stiffer brake arms, tighter fit of the brakes on the bosses, long tailed brake shoes all reduce this flex, and starting with the shoes toed in compensates for it.

    So much for the primary issue, but there are secondary causes and things that amplify problems. Any fork play is a problem. rock your bike forward and back with the front brake on and your fingers at the gap in the lower head cup. If you feel any movement, you need to tighten your headset.

    Other causes are dirty or uneven rims, which allow a grab/slip sort of action. Use some methanol (fuel alcohol, such as fondue fuel)on a rag to completely clean the rims.

    Now the cable hanger. Moving the hanger lower has had good results for many people, but I think it's more important with lightweight flexible forks. Your fork is more stout, and I'm not sure how much difference moving the hanger make, but whatever benefit you can get from a $5.00 part can't be bad.

    If I were you, I'd start with the shoes - Kool Stop Thinlines are nice and long and so resist rotation well - clean the rim, and check the headset for starters. Then if I still had issues, try the hanger.
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  13. #13
    Senior Member agobel's Avatar
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    I think you all have a clear shot of the brake itself. What type of replacement pad do I need? I'm noticing a lot of different types of studs available on "mountain bike" pads on eBay, but I'm not sure if these are interchangeable with what's on my brake now. Again, brakes are still foreign to me compared to derailers. Thanks for the help.
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  14. #14
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    You use standard threaded shoes, and have many choices, from KoolStop and many other companies. Make sure you get shoes with concave/convex washers so you can align them perfectly. I think that long tailed shoes with the mounting bolt in the forward third (see pad on top left of the KoolStop site)will help reduce shudder, but that's your call.

    I think that the best choices and value for your bike may be a Salmon colored Thinline or Eagle Claw-2 (threaded post), but there are many other good options from folks like Jagwire, Swiss Stop, and others. There are also options of shoes with replaceable pads which may cost more up front, but save money later on when you only need to replace the insert.
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  15. #15
    Senior Member Mauriceloridans's Avatar
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    The last paragraph of post #12 gave you that answer. Maybe you don't realize "pads" and "shoes" are interchangeable terms.

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    Quote Originally Posted by Mauriceloridans View Post
    The last paragraph of post #12 gave you that answer. Maybe you don't realize "pads" and "shoes" are interchangeable terms.
    In English brake shoes has always been the term of choice for bicycles just as it is in automotive and industrial. it's the same for most languages except that the French and Italians prefer to think of them as skates.

    Pads has become a popular term and usually means the same thing, but not always. What you need to be clear on is whether you're talking about an entire unit that bolts to the brake or only to a slide-in insert for shoes with replaceable pads.
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  17. #17
    Senior Member agobel's Avatar
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    Quote Originally Posted by Mauriceloridans View Post
    The last paragraph of post #12 gave you that answer.
    I see now, thank you. I sort of skimmed over the list of brands and missed the "threaded post" bit. Without getting into a semantical debate, I do realize "pads" and "shoes" are synonymous.
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  18. #18
    Senior Member BCRider's Avatar
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    For some oddball reason "pads" came into the automotive lingo back when disc brakes became more popular. Even now automotive parts guys will refer to "brake pads" and everyone knows it's for front disc brakes while "brake shoes" is for the still commonly found drum brakes on the rear of cars and trucks.
    Model airplanes are cool too!.....

  19. #19
    Senior Member agobel's Avatar
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    Quote Originally Posted by FBinNY View Post
    I think that the best choices and value for your bike may be a Salmon colored Thinline or Eagle Claw-2 (threaded post)...
    Thanks for the specificity. Will probs go with the Eagle Claw-2. None of the auctions seem to include concave/convex washers, but my current pads already have them. Those should work, right?
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  20. #20
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    Possible solutions:

    -Check headset
    -Toe your pads
    -replace and toe your pads
    -Fork mounted cable hanger
    -replace brakes


    I would try things in that order

  21. #21
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    Quote Originally Posted by agobel View Post
    Thanks for the specificity. Will probs go with the Eagle Claw-2. None of the auctions seem to include concave/convex washers, but my current pads already have them. Those should work, right?
    They may not mention them but the EC-2 shoes include convex/concave washers. I think Kool Stop uses some kind of house trade name for them - a rose by any other...
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