lhbernhardt

Hi folks,

Well, after experimenting with cantis and linear pulls (both standard and mini-V's, with and without Travel Agents) on my tandem, and after having installed a set of the carbon fiber Tektro R750's on my single bike, I am slowly moving toward the conclusion that dual pivots might be the way to go on my tandem as well. They seem to offer far greater leverage than single-pivot sidepulls, and I have been less than happy with the linear-pull options I have tried.

Unfortunately, the required brake reach may be excessive. However, Tektro has just come out with an extra-long reach dual pivot (Model #800). This has a reach of 61-78mm, which would work on my steel Kuwahara tandem. The next smaller model is the standard reach 521a, 47-57mm. However, unlike the 521a, the 800 doesn't have a quick release, it's less than half the price of the 521a, and it looks kind of cheap, kind of like the old, cheap Weinmann sidepulls of days gone by. The QR issue is not a problem, I use Campag Ergo levers. But I wonder if the brake caliper arms would flex or shudder under load. I remember listening to cheap brakes vibrating years ago. I'm thinking of trying a set on the rear. What are your thoughts? Thanks.

- L.

JayB

I'm not very technical - and still have DiaComp cantis on my only tandem, a 20 year steel model with twin laterals! However, there have been some interesting postings on the Hobbes list which started with Bill of Santana saying that dual pivots were OK only if you got the top of the line Record or DuraAce. I found this interesting because I had always thought that in the Shimano line, Ultegra was at least as strong as DA but just heavier. I hope some of the more technical contributors to this forum will give there opinions. Here is a reference for Bill's original posting:
https://hobbes.ucsd.edu/tandem/hyperm...ay06/0274.html

stapfam

It is not only cheap brakes that vibrate. I prefer to use Shimano on linear brakes, but one of the problems has been Vibration and noise. As soon as I changed off the Shimano blocks- no vibration and a lot less noise.
Then on my Hope Disc brakes I often get squeal but that is down to using the sintered pads. These are the hard form of the pads that Hope make but no problems on braking effect- just the squeal that lets people know that we are braking hard behind them.

TandemGeek

Take everything Mr. Bill has to say with a grain of salt. Here is a link to the original post AND the replies (a few are less than cordial): https://search.bikelist.org/query.asp...MsgDate%5Ba%5D

Much of what Bill posts is interesting, informative and bears some consideration; however, a lot of it is theoretical with unstated premises, no supporting data, sometimes junk science and often times factual omissions. His writing style on Hobbes (which is also this way in his annual Santana catalogs) has been this way for the 13 years that Hobbes has been in existence and always has a polarizing effect. He and I usually end up talked at length over the phone after he makes postings that get my attention and they usually end the way they start: we agree to disagree on certain things.

While well intended, at their core Bill's posts are marketing pitches that, in and of themselves, wouldn't be all that unusual; however, buried in his writings are some times claims that often times are hard to substantiate along with a stream of innuendos that suggest his competitors products are substantially inferior and in some cases unsafe. In practice, the "inferiority" of his peers products doesn't bear out in the real world for the vast majority of owners (which is to say that the superiority of Santana's doesn't necessarily manifest itself either) and the degree of variabilty in quality and/or design differences between Santana and his primary competitors is on par with the old Pepsi challenges from years ago.... In other words, personal preference and taste is often times the only thing that makes a Santana better or worse than a Co-Motion, Burley, Trek, Cannondale, Bilenky, or any brand of tandem when comparing comparable models.

Bottom Line: Santana makes some darn nice tandems, but so do their competitors. There is no such thing as "the best" when it comes to tandems... only what's best to you. Like what you ride, and ride what you like.

TandemGeek

This model?


While you don't really need a super-strong rear brake on a tandem, you don't want to use truly cheap components... and this JDM (Japanese Domestic Market) model looks less than robust... as you said, reminiscent of the old Weinmann brakes where toe-in was adjusted by bending the arms with an adjustable wrench.

To put this into context, we run Campy Record & Chorus brakes on our road tandems. Campy used to use dual pivots front & rear and then switched to their differential brake system with dual pivot up front & a single pivot (differential) in the rear. Designed for single bikes, the premise was that dual pivots could easily over-brake and lock the rear wheel of a single bike so the added value of the extra weight & power associated with the rear dual pivot was wasted. The single pivot differential brake was something like 40grams lighter than the dual pivot and did not reduce the useful braking power of the brakeset. However, on the tandems it was easy to tell which tandem had the front & rear dual pivots and which one had the single pivot differential out back... it was significantly less effective, partially due to the loss of the added mechanical advantage of the dual pivot and to deflection from the less robust brake arms.

Bill G

Very well said and so true, I take what Mr Bill has to say with a grain of salt as well. He has a sort of slanted writing style and tends to talk other tandems down a lot and play up Santana as the only good tandem out there. I find it best to read between the lines and do some research of your own. His style maid me look at other brand tandems over Santana in the first place.

Take Care and ride together,
Bill G

gm1230126

Sidepull let alone a dual pivot variety is never going to stop as well as a v-brake, canti, u-brake or disk.
There is too much stress on that single mount bolt with a tandem load when descending. There's also too much flex on a brake arm that's long enough for 80mm of reach.

operator

Would disc brakes be an option?

P.S If you do try out those dual pivots, replace those pads immediately (they wreck rims).