sd5782 

On a 1982 Trek 412, I recently switched from the stock 27” rims to 700c. I was still able to run some Weinmann 610 center pulls. They have the pads near the bottom with the rear slightly less so. My main gripe was having the center pulls not opening wide enough to take out the 35mm tires I have on it. This even with a QR on the hanger and another on the lever.

I got some Tektro 559s and just put them on. They seemed very nice, but the pads were at nearly the tops of the slots. Plenty of tire removal clearance now with the Tektro QR plus the one on the lever. I was then thinking perhaps the 539s at the bottom of the pad slot would look better. It kinda looks like either would work.

So the question is wether it’s better to have the pads at the top of the slot on the 559s, or the bottom of the slots on the 539s? That also brings up the question of if the 539s will open as wide as the 559s? This condition is exacerbated because my Weinmann concave rims are the narrower 20mm OD version and not the wider ones.

delbiker1 

I have used both models, but on different bikes. Both sets work well, but if I knew the mid reach 539’s would fit the rims, I would choose those over the 559. Pretty sure the shorter arms will provide better feel and stopping power.

ThermionicScott 

Tangential, but I manage this on centerpulls by popping the yoke off the straddle cable after opening the QR. Plenty of clearance that way!

Andrew R Stewart 

To answer your question best I can- I suspect the caliper that has the longer arms to the cable anchor and casing stop will have the greater "power". This assumes that the other lever arms in play (and that's all non cammed systems are WRT the base mechanics), the two both have the pads positioned in the slots to contact the rim and the location of the arm pivots relative to all this would be the same. For a single pivot caliper there's only one pivot and it's distance from the rim brake track center is the same for both sides/pads/arms. Thus with a single pivot caliper the one with the longer cable acting arms are the greater the leverage. But with two different dual pivot calipers the dimensional assumptions can cause real life being different as all the real lever lengths are measured and compared. I'll also say that rider perception is not always in agreement with the measured numbers.

As far as pads not opening enough for wide tires goes- On my 32 and narrower tired road bikes I run Shimano R600 calipers with their QR and Ergo levers with that QR too. On my touring rig, the tandem and the Mongoose Tomac MtB I have cantis, thank you. In all seriousness consider wider rims the next time around as the QR range starts only after the brake is adjuster properly and the wide tire and narrow rim combo will exceed this most every time (or for the calipers designed when 23/25 wide tires were the cat's meow, note I don't say when sold...). Of course the annoying solution is to deflate the tires and/or use your hand as a hammer and hope the pads stay put. Andy

sd5782 

Thanks on the replies. On taking the cables out of the straddle yoke, I have found that to generally be a major pain, but I do understand.
Yes, wider rims would be a nicer solution too, but I already have the nice looking concaves. The 559s do seem that they will be fine and no new parts would be needed. I guess I was trying to think what would be perfect while cooped up in the winter deep freeze. Those Tektros do seem nicely made and very user friendly to set up. I can understand why they are often recommended. If I ever see a set of 539s at a swap though I will jump on them. Can’t have too many spare parts.

79pmooney

Another trick - brake levers with QRs in addition to the caliper QRs. I'm guessing not an option with brifters though it ought to be. I think there are also in-line barrel adjusts with QRs. Don't know that but if not, a nice little project for an inventive type.

79pmooney

Different calipers are quite different in how hard that is. I find Weinmanns hard with cold hands and much prefer to do it with tools like a screwdriver but the Mafac Racers very easy. Especially so if you can find the straddle cables with the little tab below the free end.

Andrew R Stewart 

The Campy (and Sachs, I have a few) Ergo brake levers do have a QR function. Like Tektros and Cane Creeks (that are not brifters too) there's a sliding post just ahead of the pivot at the top of the brake blade. Andy

79pmooney

Thanks! I knew there was good reason to go Campy standard when I went 130 spacing and 9-speed on my custom. And a ti-welded "braze-on" for the top-mounted DT friction shifters. Dave Levy also put cable stops on the HT in case I changed my mind. (The real driving forces were never, ever putting those goofy horizontal brifter cables out in space a la early Shimano. That and the knowledge that the day would come that I would accidentally shift as I went for a WB or jersey pocket as I have been steadying the bike with my fingers on the side of the brake lever forever as I go one-handed.)

BTinNYC 

My 539s are going on a 27 > 700c conversion and they open up to 32mm. Pads are not quite bottomed out on my setup.

SurferRosa

Pads at the top of a modern long-reach brake in a nice vintage frame make for a really ugly, thoughtless looking solution. Use the 539.

sd5782 

It sounds like your situation was very similar to mine with regard to brake reach. That.s what I was thinking on how far they open. I do however have another QR on the lever, so perhaps the 539s would open far enough despite the narrow 20.5mm rims with the 35 Paselas. The 559s with both QRs open up nice and wide.
I do agree wholeheartedly on this, and will be on the lookout for some 539s too. I at least have to try out the feel of this setup first. You purists will be offended by the turkey levers anyhow, but my age and flexibility dictates riding on the tops mostly. You will get there some day too if you are lucky.

ShannonM

If we assume that the slotted portion of the caliper arm is the most flexible part, (because it's got a big hole in the middle of it,) then it follows that minimizing the amount of hole between the pad and the top of the hole would minimize bending between those two points.

I can't see how anything below the pad attachment point could possibly matter... unstressed aluminum, just along for the ride.

In reality?

Which ever one looks better is the right answer, because there's unlikely to be any functional difference that matters.

--Shannon