Brad Bedell

Indeed, part of the problem may very well be me or my selection of components or a combination of both. I'm sure I'm within the design parameters, but I tend to nitpick and tweak with things until I get them how I want them.

The rear derailleur is dead on; I was very concerned about tossing $500 worth of derailleurs in the trash when I had them both apart and was drilling/cutting on things. However, once it was done I was very pleased with the finished part. A medium length 11s cage would be best for a 53/39 with a 12-29 cassette, even though they say it will 'work'.

I am also pretty happy if I'm only getting 3-4 gears that rub the derailleur when in low-low gearing. For now, I have the cable adjusted so that I can quiet it down on the fly. In Dallas, we don't use anything but the 53t ring anyhow. I set the bike up to handle the 39/53 with no noise in any combination of gears.


I do get chain ring rub on my Ridley, mostly because the rings I'm running (55/44 elliptical) With the stock gears (39/53, I get no rubs) Of course, this is outside of SRAM's design, so I expect it to not be perfect.

TandemGeek

Now that I think I'm getting a better picture of your component configuration, which components are rubbing?

The only thing that comes to mind is the interference you can get when the derailleur cage is too short for the gearing and/or the B-limit screw isn't cranked all the way in to create the needed room between the derailleur's jockey wheel and the larger rear sprockets. I run into that type of chain-chatter when I'm in our 32t chain ring and running a 12x32t cassette with our older (now discontinued) long-cage Campy Record rear derailleur, as the RD is really not designed to deal with much more than Campy's 13x29t wide-range cassette.

It's a minor annoyance that we only experience on the steepest climbs, e.g., stuff in the 15% and up range that we encounter only a few times a year.

JSNYC

If you don't care about running a SRAM rear derail. with a Campy 10 spd shifter, it looks like DaVinci offers a workaround (or rather, they said it's "coming soon" on 10spd shifter-10spd derail., but do have a 10spd shifter-9spd derail. solution now).

https://www.davincitandems.com/images/sram2.jpg

Scroll down here to the product description:

https://www.davincitandems.com/comp.html

Brad Bedell

Front derailleur on the inside when going from small ring to low gearing. It was this noise or a slow ramp up on the big ring. I 'bet' a bit of a custom dimple (1mm range) would fix the derailleur. However, I didn't want to think that much after feeling lucky that the rear derailleur worked so well.

Campagnolo chain rings have a better designed chain ramp; which requires less pressure to 'shift'. I think a set of Campagnolo rings would fix it also. I have LIghtning cranks ordered... I bet Tim can do a set of 135mm spiders on the right side and I just run the Campy rings...

Brad Bedell

That's a pretty cool solution. I like SRAM's handling of the rear derailleur cable. It removes a 'loop' from the housing. I've been considering getting a SRAM XX rear derailleur to do this with my road bike.

Campagnolo makes a "comp" long cage derailleur. 40t max capacity. They also have a medium cage Record, centaur and chorus derailleur. Not sure if it's last year's stock or not, but that stuff should be available as NOS if it is.

TandemGeek

These work 'pretty well'; much better than the J-Tek shiftmates if only becase you don't get the cam-walk that can occur with the J-Tek. However, like all cable-shifted tandems, the real evil that can throw off shifting is the derailleur cable drag and/or stretch that you get with that very-long derailleur cable. The latter is probably why Shimano's Di2 holds some much promise for tandem owners who are looking for that perfect shift that only a servo-driven, smart cable-less system like Di2 or the hoped-for / still in development Di3 could provide.

As for the newer C0-0 Campagnolo 10 Speed Shifters and Shimano/SRAM 10 speed Cassette that's listed as 'coming soon' on their Website, best bet would be to call up Todd or Brian at daVinci to confirm that it's now available. I think it is, but woudn't swear by it.

TandemGeek

The consumer-desire here is having the ability to use Campy Ergo shifters with the wide-range Shimano and SRAM MTB cassettes, e.g., 12x34t. There have always been tricks of the trade or gadgets to modify cable pull that allow you to mix and match Campy shifters with Campy or Shimano rear derailleurs and Shimano / SRAM cassettes, and this was daVinci's way of integrating the gadget with a pretty nice-quality rear derailleur.

As noted elsewhere, I've always played in the narrow shifting margins that exist between Campy & Shimano cassettes by using Campy Ergo levers with Campy rear derailleurs without any modifications or tricks: I can run Shimano 9, Shimano 10 or Campy 10 interchangably with just a change of the cassettes (or a freehub/cassette) and chains plus a little fine-tuning of the barrel adjusters. Yes, there will occassionally be a little chain chatter in one or two gears, but it's easily trimmed out with just a little finger pressure on the right hand Ergo's shift lever or paddle.

JSNYC

Hadn't thought of Di2 on a tandem--that would be pretty unreal, esp. for the reasons you mentioned.

I tried it once (Di2 on a road bike, that is), and it's pretty sharp. If it trickles down to Ultegra level pricing, now you're talkin'.

Brad Bedell

A gutted pair of DI2 bar end shifters and some creative epoxy work on a left campy brake lever or custom mount on the handlebars would make for a real slick front derailleur solution.

rdtompki

Much more expertise in the above posts than I can hope to muster, but just by way of reference: our daVinci uses Campy Chorus Ergo shifters. The RD is a modified SRAM x9 unit which shifts any of the 9-spd cassettes I've tried flawlessly. The FDhandles a quad-ring 1/2-size chainring with what I believe is a custom FD. FD is not indexed, but after about 1000 miles and 1000 curses I got the hang of it. FWIW I much prefer the Campy shifters of the Shimano 105 brifters on my single, but the Shimano shifts flawlessly as well. I'll switch to 10-spd when my tandem LBS is convinced it works well enough; we're not a particularly strong team so I'm not going to worry about durability and our longer chainline gives us more cross-chaining latitude.

Brad Bedell

RV: https://www.ebikestop.com/campagnolo_...96.php?cat=494

Not *sure* what that does, didn't get enough time to look into it. However, that part is one of the parts that I drilled/modified for the 10/11 speed derailleur hybrid.

uspspro

It adds a couple of holes for the spring tang to change the tension.

https://www.youtube.com/watch?v=2NPNf...layer_embedded

uspspro

Just pondering about Di2

I wonder if you could get away with running Di2 with:
- 53/38 rings on a standard double
- 11-36 SRAM XX 10-speed cassette

38t is the smallest that will fit on 130mm BCD. The 38x36 gets you down to 27.8 gear inches which puts you right between a 30x28 and a 30x29.

That said, you could do the same with other groups... say SRAM Red.

A cool combo might be something like this:

Cranks: Lightning tandem set with 130BCD
Shifters: SRAM Force or Red
FD: SRAM Force
RD: SRAM XX
Cassette: SRAM XX

WheresWaldo

Here is the problem with Di2 and wide range rear clusters. The DA derailleur body is not set up to handle a rear sprocket larger than say 28 or 29 teeth. The Shimano spec, IIRC, is 27 tooth maximum but you can usually fudge a tooth or two. With that said, most likely the largest rear cassette you can use is the Shimano 12-27 or SRAM 11-28 without running into problems.

Please note this is not a long cage vs. short cage issue, it is an issue with the movement of the derailleur body. You will have the same limitations on SRAM Force or Red RDs.

I am a big fan of Di2 and think it would be ideal for tandem use provided they get it to work with a derailleur like an XTR that can handle a wider range cluster and they bring the price down to the current DA level.

uspspro

I thought about that, but then I saw this: https://www.cyclingnews.com/features/...ail-on-display

So yeah, RD body was the reason I listed a SRAM XX RD instead of Red/Force.

Just food or thought. I mean I am happy with my setup, but XX really makes it possible to shed some grams while keeping a wide range, and it is directly compatible with SRAM road levers.

WheresWaldo

One small correction, SRAM XX like all of SRAM's latest offerings has a 1:1 cable actuation which is not the same as Shimano so you cannot interchange levers.

uspspro

corrected.

Brad Bedell

Cool, that's basically what I 'built' with the drill press. to make the longer cage work with it. This part would have saved me about 10 minutes.

Ritterview

Just using this extant thread to note that Competitive Cyclist has a terrific promotion on 2010 Campagnolo.