Classic & Vintage - Toe-In Adjustment on Old Weinmann Centerpulls?

So I've replaced the brake pads on four of my vintage rides with the Kool Stop Continental pads. They stop great but the front brakes (only the fronts) squeal like I've never heard. I've cleaned the rims and sanded down the pads to no avail. It seems like I need to get them toed-in properly to eliminate this, but there's really no way to do the adjustment short of bending the calipers, which I've been warned against. Any ideas? Or just scrap the pads and go back to the old-fashioned DiaCompe gray pads, which for some reason don't seem as prone to squealing? Thanks.

So I've replaced the brake pads on four of my vintage rides with the Kool Stop Continental pads. They stop great but the front brakes (only the fronts) squeal like I've never heard. I've cleaned the rims and sanded down the pads to no avail. It seems like I need to get them toed-in properly to eliminate this, but there's really no way to do the adjustment short of bending the calipers, which I've been warned against. Any ideas? Or just scrap the pads and go back to the old-fashioned DiaCompe gray pads, which for some reason don't seem as prone to squealing? Thanks.

You can toe in your pads by contouring the face of the pad with coarse sandpaper.

Another common problem is not that the pads are toed out, but that the caliper is tilted so as to toe-in one pad while toeing-out the other pad. Often this can be corrected by loosening the mounting bolt and tilting the caliper within the freeplay of the bolt in the hole in the fork crown.

As always, a grippier interaction between pad and rim will increase the tendency to squeel. Many, many variables contribute, including rim material, anodizing, pad material and even humidity.

Lastly, a bridge plate "brake booster" in front of the caliper can be fashioned from aluminum sheet stock, which prevents the bolts from splaying out under increasing lever force, thus limiting toe-out. Longer bolts are needed, and these calipers are a little difficult to re-assemble with the springs.

And I believe you are correct about hesitating to bend in the arms. The plastic bushings will become distorted/loosened, and the pivot sleeves will rock against the aluminum bridge, causing a loss of surface squareness between the mating parts. Tightening the bolts to compensate results in pivot binding as the ends of the pivot sleeves become mushroomed, which is a pita to repair.

I had this problem when I tried upgrading my brake pads on my vintage bike. The response I got was the old brake arms aren't strong enough to absorb all the virbration from the longer Kool stop pads. So you just have to stick with the old ones.

Old thread link (http://www.bikeforums.net/showthread.php/676822-Centerpull-brakes-Squeal-on-new-Al-rims)

One more thing about the pads, the modern designs all seem to have the orbital washers that can allow adjusting in any reasonable abount of toe with no bending. Vintage-style pads may thus require the belt-sander treatment to effect the needed toe-in setting for the particular conditions.

Whoever warned you against bending the arms is mistaken. I've done it hundreds of times to Weinmann calipers. Never had a problem.

Whoever warned you against bending the arms is mistaken. I've done it hundreds of times to Weinmann calipers. Never had a problem.

+1. Park even makes/made a tool for it.

Whoever warned you against bending the arms is mistaken. I've done it hundreds of times to Weinmann calipers. Never had a problem.

+1

For older caliper brakes this is the standard method for toe in. Park even made a tool specifically for bending the caliper arm.

EDIT: Jim beat me to the punch! :D

Whoever warned you against bending the arms is mistaken. I've done it hundreds of times to Weinmann calipers. Never had a problem.

True, you won't notice any problem right away, especially since the squeeling goes away.
But, if you've dealt with Weinmann calipers over time, and had to later tighten the bolts (only to cause binding), then you might hesitate to fix the squeeling the easy way, especially as today's better pads have not only the orbital adjustment but can be found with heavily offset pads which directly counteract the same twisting forces on the bridge and posts which contribute heavily to squeeling.

The Park tool could thus be said to be useful for toeing caliper brakes other than Dia-Compe/Weinmann centerpulls, which are unique in having the pivot sleeves not part of the caliper bridge, but rather stabilized on their narrow ends by bolt forces alone.

No, I've been doing this for 35 years and haven't had any such problem.

I'm with Tom and Jim on this; been doing it since Weinmann/Dia Compe centerpulls were state of the art.

Top

I bought some of these pretties to try on the older brake calipers.

http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&_trksid=p4340.l2557&hash=item51a051e9ca&item=350582073802&nma=true&pt=Cycling_Parts_Accessories&rt=nc&si=grSb1cxOzQjpMenfiORigvqx9qI%253D&orig_cvip=true&rt=nc#ht_500wt_1180

J

The Park tool could thus be said to be useful for toeing caliper brakes other than Dia-Compe/Weinmann centerpulls, which are unique in having the pivot sleeves not part of the caliper bridge, but rather stabilized on their narrow ends by bolt forces alone.

The Park caliper tool doesn't fit current dual pivot brake calipers because the arms are too thick for the slot in the tool... that's why you find the toe in adjustment via the brake pad.

Still... as noglider has said and I will concur; mechanics from the 60's to the 90's have bent the caliper arms for toe in hundreds of thousands of times.

I take the wheels off and use a Crescent wrench with duct tape on the jaws to avoid marring the brakes. I can't say I've ever bent Weinmann center pull arms. I've never owned a set.

Even though the Park BT-3 tool has been discontinued, some places apparently still have it: http://www.xxcycle.com/php/boutique/page.php?nom=PRODUITpp&key=2371

http://www.chainreactioncycles.com/Images/Models/Full/13231.jpg

Based on what the tool looks like I think an adjustable wrench would also do the job.

Even though the Park BT-3 tool has been discontinued, some places apparently still have it: http://www.xxcycle.com/php/boutique/page.php?nom=PRODUITpp&key=2371

http://www.chainreactioncycles.com/Images/Models/Full/13231.jpg

Based on what the tool looks like I think an adjustable wrench would also do the job.

You are correct; an adjustable would do the same thing. So would a large flat bladed screwdriver.

I still have my BT-3 along with my OBW 1, 2 and 3 side pull caliper wrenches!

One more thing about the pads, the modern designs all seem to have the orbital washers that can allow adjusting in any reasonable abount of toe with no bending. Vintage-style pads may thus require the belt-sander treatment to effect the needed toe-in setting for the particular conditions.

Slight clarification-
To add adjustable toe functionality on vintage brakes, you can use threaded post style pads intended for MTB V-brakes. Replacement 1-piece holder/pad for these usually will include the matching convex/concave washers that allow or adjustment.

Here are two photos, showing the angle of the calipers on my 1974 Raleigh International with original Weinmann 610 center-pull brakes.

The rims are original polished aluminum, though the brand decal is gone.

The braking is entirely noiseless and very good.

The pads are Weinmann Brev.

I bought this bike one year ago from Vic (vicsclassicbikes.com) in Louisville, KY
for way too much money, but I love it. Best riding roadbike I've ever had.

If I'm replacing the pad I usually put in a kool stop eagle 2 with threaded posts, seems to work for me. I've also just used an adjustable on some of them too.

I use Kool Stop Thinline (salmon) shoes on my commuter with Weinmann 610/750s. They, the Supra model, and maybe some others have radiused cup/cone that allows the shoe to be rotated to get toe-in and also to align them vertically, so that they contact the rim surface squarely. I like this feature a lot, though I've bent arms before, even on a pair of Campy Super Record calipers -- that works too. Even adjusted with toe-in, I've found that the Kool Stop shoes will squeal for awhile, until they're worn in a little and seated. This may be a function of their "grippiness," as noted by dddd above. And even when broken in, they'll squeal on a really humid morning, or right after I've cleaned the rim braking surfaces with isopropyl alcohol.

Even though the Park BT-3 tool has been discontinued, some places apparently still have it: http://www.xxcycle.com/php/boutique/page.php?nom=PRODUITpp&key=2371

http://www.chainreactioncycles.com/Images/Models/Full/13231.jpg

Based on what the tool looks like I think an adjustable wrench would also do the job.

I'm glad you think so since that's what I've been using for the last 40 years.

Yes, the Park tool seems to be a solution in search of a problem, as an adjustable wrench works just fine.

I've been using the Kool Stop Cross pads/holders with adjustable toe in on my Campy NR brakes for a few weeks now, and really like them. I have both the black and salmon Campy inserts, but like these better.
http://www.amazon.com/Kool-Stop-Threaded-Triple-Compound/dp/B0025UJYFA/ref=sr_1_1?ie=UTF8&qid=1346162717&sr=8-1&keywords=kool+stop+cross


(http://www.amazon.com/Kool-Stop-Threaded-Triple-Compound/dp/B0025UJYFA/ref=sr_1_1?ie=UTF8&qid=1346162717&sr=8-1&keywords=kool+stop+cross)Nice International Peugeotlover! I sometimes miss my old one, and might buy it back.

'nother arm bender here...

I typically use an adjustable wrench with some sort of padding to hold the arm and a large flat blade screwdriver or another adjustable wrench to give the bottom of the arm a tweak. That is the way I was taught back around 1970.

Aaron :)

I've always used a cresent wrench, didn't even know they made a tool for this.

If you're committed to the bike being and looking period correct then I suppose bending the arms or using half of a washer as a shim are your best options. If a modern pad and holder are fine by you then that's really the better option. I use the Kool Stop Dura type holders and dual-compound pads.

http://farm9.staticflickr.com/8281/7868631702_46b9d878df_b.jpg

...too sexy for my shims...

If you're committed to the bike being and looking period correct then I suppose bending the arms or using half of a washer as a shim are your best options. If a modern pad and holder are fine by you then that's really the better option. I use the Kool Stop Dura type holders and dual-compound pads.

http://farm9.staticflickr.com/8281/7868631702_46b9d878df_b.jpg

Thanks everyone for the ideas - I've ordered a couple of different types of pads (including a pair like the ones above) and will give them all a try. Failing that I guess I'll start bending the calipers. I'm using my LeTour kid-Chariot-puller as the test subject so no great risk. Whatever works best I'll carry over to the other bikes...

I used to hate squealing brakes, but now I find that I use the squeal sort of like a bell, to wake up people in my way.
Pretty picture Colonel.