chapel

So, I've only ever had bikes with single pivots and cantis... I just bought some Tektro R539s to replace my Shimano bottom-of-the-barrel sidepulls

What can I expect? What are the pros and cons of dual pivots?

I'm hoping for enhanced brake feel and response. Right now my brakes, even with new pads and ceramic rims, are iffy to stop. I've got the calipers set up properly with the cable, but they seem to drag a little after actuating them.

Hudson308 

Many vintage sidepulls seem to lack any means to keep the caliper from rotating against the crown/bridge. The result is that they sometimes will move away from center and stay there after being actuated, with one shoe dragging slightly on the rim. My Diacompe G (sidepulls) have a double-serrated washer to keep this from happening, as well as flats machined into the caliper pivot sides that enable a 12mm cone wrench to be used to hold them in position when tightening the mounting nut. I've never owned dual-pivots, but I would bet they would at least hold their centered position better.

surreal

My experiences: easier set-up with dual pivot, but the trade off is more frequent small adjustments of the pads to keep them from "riding up" on the rim.

Single pivots never gave me the same nice, positive feel at the levers as dual pivots, although I could get close with some tuning...

mechanicmatt

IMHO They stop better. Not exponentially better, but a good bit better. I have several bikes with different sets (Shimano, Tekro) but the best pair I have is a pair of dual pivots by Tektro with Kool Stop Salmon Pads. I can actually lock up the wheel if needed on those.

When I was a cheap skate college kid, to upgrade my road bike, I just upgraded the rear brake to dual pivots, as I just needed a drag brake out front.

The Golden Boy 

I replaced a set of single pivot 'lower end' Shimano calipers with a set of TriColor 600 brakes- Dual Pivot in the front and Single Pivot in the back.

I think I have a greater amount of modulation- more ability to slow down as quickly or slowly as I wish to. I also think I have greater stopping power. I think the force of the lever pull is better transferred to the "newer" brakes.

I ran into a couple of problems- and I don't know if either will apply to you.

First- the Shimano SLR brakes don't have a strong spring return- where a normal old brake relied on the caliper spring return to pull the lever back to the starting position- the "newer" brakes don't the levers have a return spring in them. So you *may* need new levers to "match" the brakes.

The other issue was the amount of reach- make sure your shoes have enough reach from where the mounting hole is.

Phil_gretz

Ease of centering. There'll be a set-screw built into one arm of your dual pivot caliper, with a 2.5mm hex head, that adjusts the right-to-left centering. Just use the mounting nut to get the caliper close to centered when mounting.

Of course, you might find that your Centurion isn't drilled for the recessed end nut. Although it might be by 1987 - I don't know your frame. There are various forum threads on how to do the drilling if needs be...

chapel

I have Retroshift levers (which are modern Tektros)
The R539s have the same advertised amount of reach as what I have now. *crossing my fingers*

I went with the R539s because they were available as a nutted version (which is what I'm 'stuck' with because I don't feel like drilling...)

thinktubes 

You can expect to "lay a patch"

RobbieTunes

Better feel, better ability to modulate, better stopping power, easier installation. That's about it.

avzay66

much better performance. I upgraded my side-pull weinmanns to tektros, the stopping power increase is major. Looks not too bad either.

spacemanz

They feel a lot sturdier, if that's the right word, which makes you feel a bit safer & more confident. They set themselves up pretty well really, but I've found that the best way to get the pads & cable & everything really dialed in, is to apply light pressure, while adjusting both pads, to get all the adjustments right (look at it good), and the same thing while clamping & adjusting the cable (some steps you do twice or more, if needed). That doesn't sound like I wrote it right, but once you do it, you'll see what I mean. Locking up the brakes is easy, if you want, but the trick is learning modulation, to stop smoothly. That's probably more important, in wet weather, like Seattle, where hydroplaning can be seen pretty often.

Bikedud

+1

I tried to keep my beautiful Suntour Superb Pro brakes on a recent rebuild of a mid eighties frame for aesthetic reasons. Apparently I have become too accustomed to DA and Ultegra dual pivot brakes. I just couldn't adjust (re-adjust?) to poorer overall performance of the Superb Pros.

old's'cool

No doubt the DPs are newer, better technology.
I will quibble with "better stopping power" in that a decent single pivot system has enough braking power to easily stop either wheel and respectively skid the rear tire or send you over the handlebars (or send the front wheel out from underneath you, depending on traction).
I see greater force multiplication (offered by DPs) as a major benefit on long and/or steep descents, when hand muscle fatigue could become an issue due to intense and/or prolonged braking.

spacemanz

That's it in a nutshell. Once you get the DPs really adjusted, you can brake with one finger on the lever, or maybe 2 on downhills.

RobbieTunes

Exactly. I clamp, adjust, clamp, adjust, fine-tune until I am sure that both pads are contacting the rim at as close to exactly the same time as possible. This solves so many issues and makes modulation so much easier.

And I always use the serrated edge washers. I have no idea if that's a good idea or not, but I hate the calipers moving around on the fork or bridge.

I think a wrench once told me about single pivots, "you need them to be sloppy equally on each side."

Funny, but almost every tri-bike build I do, I find a set of single pivot 105's. Light, small, and stopping is not a requirement for a triathlon bike; the dismount is at a run.

orangeology

less C&V looking—subjectivity pending.
#tradeoff