Classic & Vintage - Bent brake caliper? Suggest to me my options..

Hello

(Not sure if this is the right place to post this but here we go..)

I recently acquired a old Bianchi (Campagnolo Nuovo Gran Sport derailleurs) and the Modolo Flash front brake caliper is bent (I think). I took a photo because I'm not great at explaining things..

http://img502.imageshack.us/img502/6800/17191356678svkfb.jpg

The right arm sits back a little and seems to sit at an angle, bad enough for the end (the side closest to the fork) of the brake pad to not fully hit my rim.

Is this fixable?

If not, what do you suggest as a replacement?

From what I have gathered online, I believe the original brakes were Universal 77. I don't know much/anything about brakes and so would value any opinions and suggestions as to what to replace with..

(center bolt to center of rim measurement is 55mm).

Thanks :thumb:

Remove the pad and gently twist the arm using a adjustable wrench.

Remove the caliper, it may well be that the mount hole for the brake is off, not the caliper.
If the nutted type the check is easy, just slide a plus screwdriver with a shaft of a similar diameter and observe, if allen key fittings, then a bit more effort.
While the caliper is out check the pivot bolt for a bend. Modolos go together a bit differently than other brakes, one way to check the bolt would be to release tension on the caliper spring, then rotate the brake bolt.

One side comment, I have two bikes that have the fork drilled slightly off, both of those bikes have never had squealing front brakes.

Aluminum alloy brakes, and how much bending they can tolerate, are a topic without much consensus. My own opinion is that they can be bent to achieve "toe-in" (front edge of brake pad contacting brake track on rim before the rear edge), while others feel that's dangerous, and prefer shimming the brake pad or sanding the wearing surface down to achieve the same thing. What you have in the photo looks like the left pad had no toe-in, or might even be toed out, and the right pad is toed in too much. Have you checked to see whether the bike has sustained a frontal collision? (Signs: bends or paint cracked on top tube and/or down tube behind the head tube; fork blades bent backward) In such a crash, the caliper bolt might bend; you should check that by removing the caliper.

If it were my bike, and arms were bent rather than bolt, I'd attempt to bend the arms of the caliper back to normal position. That's done by removing the brake pads completely, and using an adjustable ("Crescent") wrench with terry cloth padding the jaws on the upper portion of the caliper arms that has the slot for the pads: putting the wrench right at the top of that slot. You have to work slowly, in increments, testing where you are by re-fitting the pads.

An alternative is to replace the pads with ones that have adjustability built into them, by means of domed and concave surfaces; Kool-Stop makes these
http://sheldonbrown.com/harris/brakeshoes.html#threaded
I only linked to Harris Cyclery because I know they have a page showing the threaded stud type all shown on one page. I'd be looking at Supra2 or Thinline (my favorite). Kool-Stop's site
http://www.koolstop.com/english/rim_pads.html
shows everything and more, but not in one place. They make pads in lots of colors now, apparently; used to be only salmon and black.

Even if I went with the Kool-Stop pads, I'd try to correct the misalignment of those caliper arms. And I'd ride them slowly, and really brake hard to test whether the re-bent arms will break, before trusting them implicitly.

My "target" for toe-in on caliper brakes is typically a gap one credit card thickness at the aft end of the pad when the front is just touching, for a short pad like you've got. If that doesn't result in squeal-less operation, I add some more. When I set up the Thinline ones, which are longer, I typically adjust them by clamping the brakes down hard (tie the hand lever in compressed position), and insert two credit cards at the aft end of the pad, then tighten the nuts, holding the pad so it doesn't rotate on the stud axis.

It would actually be a great bike product if someone would simply make and sell angle shims for achieving toe-in, or else cupped/bowed washers like Kool-Stop's, but of minimal thickness.

Confession: I have broken a caliper before, but not bending the arm for toe-in, but in over-tightening the cable clamp, resulting in the arm breaking right at the neck before the clamp end. They snap off in a very surprising way, suddenly.

If you look at other pics of Modolo Flash calipers, you will see that it is not bent.

If those pads have hardened, you might want to replace them.

Thanks for the replies..

I just unscrewed the caliper and brake pads off and judging with my eyes and a ruler.., I'm fairly certain the arms are not symmetrical. So I'll attempt to bend them once I'm more certain (I'll also compare with the rear which seems to be in good working order).

To be honest though, I was kinda hoping to just replace them - they're not the best of brakes (I have to be very careful going downhill !)

If you look at other pics of Modolo Flash calipers, you will see that it is not bent.

If those pads have hardened, you might want to replace them.

I think I see what you mean but that doesn't explain why the right side is hitting the rim differently from the left? If this is the way its meant to work...then these brakes really are as bad as some say? (the pads in the picture are new, they originally has some rock hard Modolo pads in them...)

If this is so - Please suggest me some new period correct (late 70s-early 80s) brake calipers please...:)

Know that if you're buying modern brakes, you may have to drill the holes out a bit to accommodate them.

edit: Whoops. Bad timing as clearly that is a non-issue.

Oh and yes the down tube has clearly been hit (near the right shifter) by the brake..nothing major..loss of paint, and maybe its rust..but not dented. <---more reason to assume that the right caliper arm is at fault.

Ish's comment, I believe, is saying that the bend on the left-hand arm is part of the design, as it is with many manufacturers' sidepull brakes -- the arm has to bend from the front back into alignment with the right-hand arm. I also doubt that your concern about the quality of the Modolo brake is warranted, even though the Flash was not top of Modolo's line. Sidepull brakes are inherently "underpowered" compared with other types: the way this is often explained is that sidepulls are for racing, where "stopping" is not the required performance, but "modulation of speed." You can probably make them work better, giving you more confidence in them, if you set them up properly and adjust for minimum clearance at the wheel when at rest, meaning maximum lever advantage when they're applied.

If you want real stopping power, replace sidepulls with centerpull brakes; my recommendation would be Weinmann 610 and 750 ("Vainqueur 999"). The 610 means max. reach of 61 mm, while 750 is longer, up to 75 mm reach from bolt hole to rim track. You might be able to get away with 610 on both front and rear though. Weinmanns are pooh-poohed by brake snobs, mainly because they were so ubiquitous, but they were original equipment for many 70s and early-80s bikes, even Schwinn Paramounts and Raleigh Internationals.

If you can't bring yourself to go the centerpull route, or have a need to stick with Italian (Weinmann is Swiss), then try a set of Campagnolo Gran Sport calipers. They're not that expensive on eBay, and I can't tell the difference in performance between them and the more exalted (Nuovo/Super) Record calipers. As time went on (early 80s), they were marketed as "Victory" or "Triomphe" rather than Gran Sport, but these are basically the same design. And since you have Gran Sport derailers, you'll be all tidied up, gruppo-wise. You can use the same brake levers with either sidepulls or centerpulls.

What are Universal brakes like(in your opinion) ? Just wondering since thats what the original catalogs specified.

Universals are OK depending on the model. I would look on ebay, here in the forsale forum or around you locak shops for another pair of Modolos or DiaCompes or even some reasonably priced (like that happens) Campi Triomphe or Victory calipers

...Modolos or DiaCompes or even some reasonably priced (like that happens) Campi Triomphe or Victory calipers

hehe, I just saw some Campy Super Records (callipers only) on Ebay go for £175 (thats $280 USD !!). Insane.

I'm going to live with my Modolo's for now but I'll be watching out for Gran Sport, Victory, Weinmann..maybe Universals....too much choice curse :)

Thanks all

update.

I found a 'reasonable' price for a pair of Gran sport (about 50 USD)? Hope this works out well, if not I guess I can always sell it back on..

It's probably the cheapest that I will get here in the UK.