brake shutter

[don compton]

i recently put fenders on one of my bikes and installed tekro brakes to allow for easier install and removal of those fenders. however, i can't stop the brake
shutter. i have adjusted the toe-in and little or no improvement. has anyone tried the "koolstop" pads as a remedy for this problem?
don

[eddief]

are notorious for being cost effective in general and having sh*t pads specifically. not sure if different pads will solve your problem, but it is worth a try.

brake physics are pretty simple and proven so i'd bet on new pads. you might also make sure, if you have not done so, that your braking surfaces are uniformly clean and without other junk.

by the way, i have encountered situations where i had to keep screwing with the brake shoes til it worked. one toe in, one toe out, up a bit in the caliper, or down. and not just toe in and out but whether the top edge of the pad hits the rim first or whether both faces meet face on as soon as the brake are applied.

[e-RICHIE]

has anyone tried the "koolstop" pads as a remedy for this problem?
don



i use koolstops and cut their length down by half atmo.

ps

arrange disorder

:) :) :)
:) :) :)
:o :) :)

http://farm5.static.flickr.com/4086/5061919705_f5a9c70ecc.jpg

[rwsaunders]

I run Tektro CR720 cantis on a Poprad and I replaced the factory pads with KoolStops as a part of general maintenance...no more shudder or squeal. Not sure if you'll have the same effect on dual pivots.

[DfCas]

77777

[maxdog]

i use koolstops and cut their length down by half atmo.

ps

arrange disorder

:) :) :)
:) :) :)
:o :) :)

http://farm5.static.flickr.com/4086/5061919705_f5a9c70ecc.jpg

i guess you find skewer springs extraneous as well.

[johnnymossville]

I was just discussing a near death experience with a guy today about my old bike and it's el-cheapo tektro brakes, specifically the pads. Not sure which model they were.

They fade to the point of nobrakes faster than any brakes I've tried. Better pads help A LOT!

[e-RICHIE]

i guess you find skewer springs extraneous as well.
yes - they get in the way, especially in 'cross atmo.

ps

arrange disorder

;) ;) ;)
;) ;) :)
;) ;) :rolleyes:

[don compton]

i recently put fenders on one of my bikes and installed tekro brakes to allow for easier install and removal of those fenders. however, i can't stop the brake
shutter. i have adjusted the toe-in and little or no improvement. has anyone tried the "koolstop" pads as a remedy for this problem?
don
just for clarification, my bike is a 59cm rivendell roadeo. i had no shutter with my shimano std reach brakes. the tekro brakes shutter, period. my only question is, after experimenting with toe-in and not solving the problem, could using one of koolstop's brake pads ( salmon or dual ) possibly cure my problem?
don

[Ken Robb]

When I have trouble with my shutter I try a different aperture. :D

[AngryScientist]

When I have trouble with my shutter I try a different aperture. :D

http://appstorehq-production.s3.amazonaws.com/badumching-rimshot-punchlinedrumrollsoundengine-iphone-18115.185x185.1240158129.63816.jpg

[don compton]

When I have trouble with my shutter I try a different aperture. :D
hey, by the way, thanks for your help.

[spartacus]

When I have trouble with my shutter I try a different aperture. :D
:rolleyes: Is he German?

[spartacus]

Are we discussing canti brakes here, or... what?

[skijoring]

Pretty sure the Roadeo is spec'ed for sidepull calipers.

[RPS]

From their web site -- not sure it helps clarify brake type in this case.
Prototype 1 showing actual front clearance--enough for Jack Brown 33.33333333 infinity tires with fenders, no tricks, no buzzing, no fender squeezing with the brakes, because they're Tektro BM 57s.

[maxdog]

don, sorry if my irreverent post, on your thread, in reply to e-richie, was annoying. i could not resist as i hold him in high esteem in this realm. i actually tuned in here because i was interested in the constructive feedback you might get.

i can not give any advice personally, but would suggest checking sheldon brown's site or googling jobst brandt on the subject. both highly respected experts on the subject of bike mechanics/physics. good luck.

[e-RICHIE]

don, sorry if <cut>
the springs go, as does half of the pad's length atmo.
what brake shutter?

ps

arrange disorder

:rolleyes: :rolleyes: :rolleyes:
:rolleyes: :rolleyes: :)
:) :( ;)

[RPS]

just for clarification, my bike is a 59cm rivendell roadeo. i had no shutter with my shimano std reach brakes. the tekro brakes shutter, period. my only question is, after experimenting with toe-in and not solving the problem, could using one of koolstop's brake pads ( salmon or dual ) possibly cure my problem?
don
Don, the "BigMouth" or BM 57 are listed as Tektro R538s which are for longer reach between 47 and 57 MM. How were you using standard reach Shimano brakes? Did you use any kind of mounting adaptor before or now?

Not what you asked, but if you were using long reach Shimano that worked without shutter, why not go back to them? Is the clearance really that different considering the mounting is in the same location? :confused:

[maxdog]

the springs go, as does half of the pad's length atmo.
what brake shutter?

ps

arrange disorder

:rolleyes: :rolleyes: :rolleyes:
:rolleyes: :rolleyes: :)
:) :( ;)

e-richie, pm sent.

[spartacus]

Tin hat on. Is there something special about Jack Brown tires? :beer:

[FGC]

Could it be the same phenomenon that causes cantilever brake shudder condensed into a smaller package? The brake arms may be too flexy for themselves.

http://velonews.competitor.com/2010/09/cyclocross/technical-qa-with-lennard-zinn-return-to-cross_101807

Before changing pads I would experiment with every different permutation of brake pad alignment. Kool-Stop Salmon pads are actually stickier and may make it worse. Then you spent money on the problem and still don't have a solution.

[benb]

I get chatter on my F3 fork + Ultegra std. reach brakes.. I use the Kool stop salmon pads.. anything else just seems to chew up rims with all the bad weather we have.

IIRC the shimano road calipers don't have adjustable toe? Maybe I'll try this cutting the brake pad thing.. I'd have thought cantilevers would have adjustable toe and you'd be able to fix it that way.

My next question would be does chopping the pad cause a net loss or gain in stopping power? You're losing area on the brakes, but if they don't chatter it might make up for it...

I was wondering if it was rim wear in my case.. now I won't have an excuse to buy new rims. :(

I'll defend Serotta though and at least mention even though I get this problem on hard stops it doesn't seem to affect traction, stopping distance, etc.. at all. It's just annoying.

[RPS]

My next question would be does chopping the pad cause a net loss or gain in stopping power? You're losing area on the brakes, but if they don't chatter it might make up for it...
In general the amount of surface area is not all that important – everything else being equal -- because it has a very minor change in coefficient of friction, if at all. Applying the same amount of lever force simply concentrates braking friction in a smaller area with higher pad-to-rim pressure (i.e. – force/area), but the amount of stopping “power” shouldn’t be affected much if at all. What I would expect is much faster pad wear since stopping forces are more concentrated. It might even make a slight difference in rim wear rate but I doubt you’d ever notice it.

[don compton]

[QUOTE=RPS]Don, the "BigMouth" or BM 57 are listed as Tektro R538s which are for longer reach between 47 and 57 MM. How were you using standard reach Shimano brakes? Did you use any kind of mounting adaptor before or now?

Not what you asked, but if you were using long reach Shimano that worked without shutter, why not go back to them? Is the clearance really that different considering the mounting is in the same location? :confused:[/QUOTE
most modern dual pivots are short reach. standard reach are longer than brakes on i.e. a trek madone. the roadeo is designed for old "standard reach" brakes. i was using shimano r600, standard reach but wanted a brakeset that would open wider to allow for easier installation or removal of a set of fenders.
i purchased a set of tekro standard reach, dual pivot brakes and that set is not as stiff as the shimanos and tend to shutter under braking. after all the good ideas from some of the responses, i have purchased some "koolstop" pads and , hopefully, they will be an improvement.]
thanks,
don

[RPS]

Got you. When you said “standard” reach I thought you were talking about a standard road caliper.

I read on their web page that the BM 57 opens wider but don’t know how that’s accomplished. Visually the release doesn’t look that different so I’d be curious to know how it is accomplished.

[cp43]

Got you. When you said “standard” reach I thought you were talking about a standard road caliper.

I read on their web page that the BM 57 opens wider but don’t know how that’s accomplished. Visually the release doesn’t look that different so I’d be curious to know how it is accomplished.

The release is pretty similar, but the cable is attached farther from the pivot than on a normal brake. So, you get a bit more movement of the cable when you flip the lever. If you look closely at he picture above you can see it.

Chris

[shiftyfixedgear]

The Tektro 538's have a terrible design WRT mechanical advantage compared to almost any other recent brake on the market.

I had Shimanos 57's on other bikes and was always pleased with the braking response and lever feel. I bought some 538's because I read the description on the Riv website and it seemed like they would be even better than the Shimeenos WRT clearance and fenders. After installing them and riding I was amazed at the utter lack of braking power compared to the Shimanos. O.K. methinks - I'll just remove the execreble Tektro pads and replace them with some Salmon KStops. Even with the salmons AND clean, degreased and sanded rims the Tektros just plain SUCKED. They took noticeably more force at the lever (think "deathgrip") before I could stop going downhill.

I decided to ditch those POS brakes and went back to Shimano's, and what a difference. Like night and day for the better.

When I was at Interbike I picked up the 2011 Tektro brochure because they DO make many other brakes that are better performing. I saw that they now offer an updated version of the 538 - the 539, which the catalog describes in bright red letters as having a "new mechanical ratio". I have a feeling that there was more than a little feedback to them about the shortcomings of the 538 design.

All of ths babble is a long-winded way of me suggesting that even with the KS salmon pads don't expect too much from those crappy pinchers. If you got them from Riv I would return them and get something better. Sometimes there just is no tweaking a terrible design.

[don compton]

The Tektro 538's have a terrible design WRT mechanical advantage compared to almost any other recent brake on the market.

I had Shimanos 57's on other bikes and was always pleased with the braking response and lever feel. I bought some 538's because I read the description on the Riv website and it seemed like they would be even better than the Shimeenos WRT clearance and fenders. After installing them and riding I was amazed at the utter lack of braking power compared to the Shimanos. O.K. methinks - I'll just remove the execreble Tektro pads and replace them with some Salmon KStops. Even with the salmons AND clean, degreased and sanded rims the Tektros just plain SUCKED. They took noticeably more force at the lever (think "deathgrip") before I could stop going downhill.

I decided to ditch those POS brakes and went back to Shimano's, and what a difference. Like night and day for the better.

When I was at Interbike I picked up the 2011 Tektro brochure because they DO make many other brakes that are better performing. I saw that they now offer an updated version of the 538 - the 539, which the catalog describes in bright red letters as having a "new mechanical ratio". I have a feeling that there was more than a little feedback to them about the shortcomings of the 538 design.

All of ths babble is a long-winded way of me suggesting that even with the KS salmon pads don't expect too much from those crappy pinchers. If you got them from Riv I would return them and get something better. Sometimes there just is no tweaking a terrible design.
at least, i am not the only one noticing the weakness of these brakes. anyway, if the koolstops don't work with the tekros, i may use them with my shimanos and just live the hassles of removing the fenders with shimano brakes. and by the way, the roadeo is a great bike( a little heavy ) and i love riding it in the hills because it is so stable on any downhill.
don

[RPS]

When I was at Interbike I picked up the 2011 Tektro brochure because they DO make many other brakes that are better performing. I saw that they now offer an updated version of the 538 - the 539, which the catalog describes in bright red letters as having a "new mechanical ratio". I have a feeling that there was more than a little feedback to them about the shortcomings of the 538 design.
When I first read about how the Tektro 538 caliper would open much more to clear mounting of wider tires on narrow rims and/or fenders, my first thought was whether they used a different type of quick release which freed more cable, or if the mechanical advantage of the caliper was such that the same amount of cable release would open them more. Seems from the two observations above that it’s probably the latter.

BTW, I no longer see the 538 listed on the Tektro web page so it may be history.

[Ken Robb]

I wonder if Tektro sent thank-you gifts to all the folks who did the testing of the "Beta" model

[RPS]

at least, i am not the only one noticing the weakness of these brakes. anyway, if the koolstops don't work with the tekros, i may use them with my shimanos and just live the hassles of removing the fenders with shimano brakes. and by the way, the roadeo is a great bike( a little heavy ) and i love riding it in the hills because it is so stable on any downhill.
don
If you go back to the Shimano calipers, one option to occasionally open them a little more is installing inline cable adjusters (if you have the room). I’m using an inline adjuster on the rear mini-V brake on my Cannondale tandem and it does an adequate job; plus it’s inexpensive, simple to install, and easy to use. It clutters the brake housing a little more but after a while I don’t notice it.

In most applications they are used to close the caliper as pads wear, but I don’t see why you couldn’t use it to occasionally open the caliper further by installing it in extended length.

[jbay]

When I first read about how the Tektro 538 caliper would open much more to clear mounting of wider tires on narrow rims and/or fenders, my first thought was whether they used a different type of quick release which freed more cable, or if the mechanical advantage of the caliper was such that the same amount of cable release would open them more. Seems from the two observations above that it’s probably the latter.The cam on these Tektro models does release much more cable than the cam on other dual pivots:

Quick release details (using Flash) (http://www.tektro.com/_english/02_technology/01_detail.php?pid=1)

Rivendell photos showing the cam in action (http://www.rivbike.com/products/show/tektro-bigmouth-57/15-150)

BTW, I no longer see the 538 listed on the Tektro web page so it may be history.That is because it has been replaced by the 539:

Tektro R539 (http://www.tektro.com/_english/01_products/01_prodetail.php?pid=65&sortname=Brake&sort=1&fid=2)

The 539 has more mechanical advantage than the 538 and a lock on the quick-release cam.

-- John

[jbay]

i may use them with my shimanos and just live the hassles of removing the fenders with shimano brakes.Don,

What problem are you trying to solve with regard to removing fenders? The Tektros and Shimanos behave the same with regard to fitting and removing fenders. Perhaps using:

Sheldon Fender Nuts (http://harriscyclery.net/product/problem-solvers-sheldon-nut-fender-nut-set-2467.htm)

or the Berthoud equivalent would help?

-- John

[jbay]

The Tektro 538's have a terrible design WRT mechanical advantage compared to almost any other recent brake on the market.

I had Shimanos 57's on other bikes and was always pleased with the braking response and lever feel. I bought some 538's because I read the description on the Riv website and it seemed like they would be even better than the Shimeenos WRT clearance and fenders. After installing them and riding I was amazed at the utter lack of braking power compared to the Shimanos. O.K. methinks - I'll just remove the execreble Tektro pads and replace them with some Salmon KStops. Even with the salmons AND clean, degreased and sanded rims the Tektros just plain SUCKED. They took noticeably more force at the lever (think "deathgrip") before I could stop going downhill.FWIW, I have 538s on two bikes and they are my favourite brakes, bar none. While the brake pads on both are located at the bottom of the slot (i.e. least mechanical advantage), they have a different feel on the two bikes. On one, I am using the outstandingly ugly Koolstop Continental (http://www.koolstop.com/brakes/index.php#Anchor-Completely-14177) pads, which are very thick and last forever. On the other, I kept the pads holders and replaced the stock pads with Koolstop Salmons. The former setup, with the Continentals, require more hand force than the latter, but I can lift the rear wheel off the ground without undue hand force on both bikes.

Of possible note though, I am using the longest Berthoud brake nuts (http://www.euroasiaimports.com/productcart/pc/viewPrd.asp?idproduct=16235&idcategory=0) to facilitate mudguard/fender mounting. These reinforce all but a millimetre or two of brake mounting bolt and - given that sidepull/dual-pivot brakes (not to mention centre-mounted centre-pulls) flex at the mounting bolt, this makes a big difference to brake feel. With the same setup on Shimano RX100 57mm reach brakes, I don't believe I could tell the difference between the Tektros and the Shimanos.

-- John

[RPS]

The cam on these Tektro models does release much more cable than the cam on other dual pivots:

Quick release details (using Flash) (http://www.tektro.com/_english/02_technology/01_detail.php?pid=1)

Rivendell photos showing the cam in action (http://www.rivbike.com/products/show/tektro-bigmouth-57/15-150)

That is because it has been replaced by the 539:

Tektro R539 (http://www.tektro.com/_english/01_products/01_prodetail.php?pid=65&sortname=Brake&sort=1&fid=2)

The 539 has more mechanical advantage than the 538 and a lock on the quick-release cam.

-- John
Thanks John, that's good information.

Still wonder if the 539 may not open as wide as the 538 due to the greater mechanical advantage assuming they use the same QR.

[jbay]

Still wonder if the 539 may not open as wide as the 538 due to the greater mechanical advantage assuming they use the same QR.I think the q/r mechanism is the main contributor to how far the arms open, so I wouldn't expect there to be any noticeable difference between the 538 and and 539 in this respect. Not that I've even seen a 539 in the metal at this time...

-- John

[don compton]

FWIW, I have 538s on two bikes and they are my favourite brakes, bar none. While the brake pads on both are located at the bottom of the slot (i.e. least mechanical advantage), they have a different feel on the two bikes. On one, I am using the outstandingly ugly Koolstop Continental (http://www.koolstop.com/brakes/index.php#Anchor-Completely-14177) pads, which are very thick and last forever. On the other, I kept the pads holders and replaced the stock pads with Koolstop Salmons. The former setup, with the Continentals, require more hand force than the latter, but I can lift the rear wheel off the ground without undue hand force on both bikes.

Of possible note though, I am using the longest Berthoud brake nuts (http://www.euroasiaimports.com/productcart/pc/viewPrd.asp?idproduct=16235&idcategory=0) to facilitate mudguard/fender mounting. These reinforce all but a millimetre or two of brake mounting bolt and - given that sidepull/dual-pivot brakes (not to mention centre-mounted centre-pulls) flex at the mounting bolt, this makes a big difference to brake feel. With the same setup on Shimano RX100 57mm reach brakes, I don't believe I could tell the difference between the Tektros and the Shimanos.

-- John
i just replaced the pads on my 538's with koolstop salmon pads. bottom line, problem solved. thanks for all the different ideas. i have velo-orange alu fenders with the "sheldon nuts". it still is much easier, even the sheldon nuts, to be able to open the brakes very wide when removing or installing fenders.
don c.