Tandem Cycling - Test dummies . . . again!

Through our 37+ years of tandeming we've tested several new tandems and tandem related products.
Well, at ages 80/77 we're test dummies again!
Bob Davis, of Zona Engineering and Development in Peoria, AZ made us an offer we could not refuse!
Would we like to test ride the Dura Ace Di-2 electronic shifting system with a new type of battery set up?
We were using the old reliable barcon shifting method for the last 30,000-some miles after having disposed ot the D/A STI that we had some issues with.
Bob would modify our tandem and install the system at minimal cost to us. In return we had to supply feedback and voltage readings before/after each tandem ride.
Not really being into electronics, we had some questions.
We would loose our triple chainring set-up that we liked. Di-2 only accepts 2 chainrings so we switched to 48/32 ring combo; swapped our 9-speed for a 10 speed cassette (11/34) and of course had to install a new 10-speed chain.
This allowed us to keep about the same gear range we had before. Old setup's top gear was 130 inches (which at our ages we hardly used any more) and the new arrangement tops out at about 118 gear inches. Granny gear remained in mid-20s range
So, we switched from 3x9 speed combo to a 2x10 setup with satisfactory gears for us.
To be sure the change from barcons to electronic shifting is enlightening!
While at first glance the Di-2 carbon fiber shift/brake levers look a bit like STI, they decidely operate differently.
A subtle touch of the hi/lo buttons on the brake levers and the shifting is done.
Instantaneous . . . and front derailleur aligns the chain automatically with whatever cog you shift to.
The 48/34 combo or 32/11 combo? Works . . . noiselessly.
Bob routed the electronics cables from shift/brake levers under handlebar tape and then internally through lateral tube. Wires exited at rear of stoker's bottom bracket and chainstays. Routed the rear derailleur electronic cable unde chainstay and the other cable to the front derailleur.
We have about a hundred miles on the system.
So far so good . . . we are impressed!
Currently testing a Nickel Metal Hydride (NMH) Low Self-Discharge (LSD) batttery for the shifting.
Shimano utilizes a Lithium Ion rechargeable battery ususally located near the bottom bracket on the seattube.
Craig Calfee offers a battery that fits inside stoker's seatpost.
Bob Davis of Zona Engineering has expanded that by making it possible to recharge the NMH battery without seatpost removal.
Of course, we did not have Di-2 shifting on our Zona tandem, so Davis had to modify it a bit.
The electronics cables run under the handlebar tape from the shift/brake levers into the lateral (internally) and exitnear the back of the rear bottom bracket/chainstay juncture. Then externally to the front derailleur and under the chainstay to rear derailleur. A very clean looking setup.
A small connector exits the stoker's seatpost under the saddle for recharging.
Another connector under stoker's saddle allows for voltage readings to be taken during our test period.
The original price for D/A electronic shifting of about $3,500 was a bit much for most of us; introduction of the Ultegra version at about $1,300 less will have more folks consider the electronic shift option. The Ultegra is a tad bulkier looking and about 6 ounces heavier but seemingly works as well as the Dua Ace version.
As more units are sold, and other component manufacturers enter the fray, we can see these systems proliferate in the future.
Pedal on TWOgether!
Rudy and Kay/zonatandem

They did all the work of setting it up. Cost to you: $0.00. All you two have to do is ride the bike and record a few observations.

What's not to like about that?

Have fun out there on the Cutting Edge!

JanMM:
Cost was 'minimal' to us . . . but not quite $0.00!
Set up was no cost in exchange for data during the test.
So far we are impressed; much better than D/A STI that we had on our tandem for the first 3,000 miles before switching to less complex and more efficient/simpler barcons.
Currently riding in cooler Utah for a few months 'til the heat dissipates a bit back home in Tucson.
Cooler weather/cooler shifting . . . great combination!
Pedal on!
Rudy and Kay/zonatandem

if they are entrusting you for evaluation I sure could not call you dummies. Sounds like a great improvement to the di2 system. Your experience helps lots when it comes to setting up the equal or best match gearing. Best of luck to you both.

I take it that they put a long cage on the rear derailleur to allow it to work with the larger cassette?

WE think as long as no "planned" crashes are involved, great opportunity! We await results
R&J

Merlin:
Yup, longer cage on rear derailleur.
Did have a funny issue on ourt 2nd ride . . .
Rear der. made some funny sound when shifting over a couple cogs.
Checked it out . . .
Piece of nylon string wrapped into cassette!

Grace:
No planned crashes while testing . . . these old bones take too long to heal nowadays!

Fly:
Have done all sorts of testing in our decades of tandeming. Stoker Kay thought we were dummies for some of the things we tried.
Some never saw the light of day after we were done. But majority were positive.
Pedal on TWOgether!
Rudy and Kay/zonatandem

A couple of questions on the gearing: What crank did you mount the 48/32 chainrings to? If the 48 is in the middle position of a triple, then who makes a middle ring that is so big?

Doesn't seem all that different -- other than the battery -- from what Santana began using a couple years back now, i.e., compact double cranks with semi wide-range rear cassette... and more recently, wider-range cassettes with the aide of the K-Edge extra-long rear derailleur cage. 48/32 is a bit odd vs. 50/36 or 50/34. Same system Calfee, Paketa, Eriksen and other high-end customs have also been fielding.

Took me about a day and a half to get my timing down for the way Di2 shifts and found that I had to double shift a lot, which is the norm for compact doubles even on a single bike. It was nice, but didn't strike me as revolutionary. Battery life didn't seem to be an issue either, noting a full-charge would deliver something like 2,000 shifts and your battery indicator gave you plenty of advanced notice as to when a charge was required.

Doesn't seem all that different -- other than the battery -- from what Santana began using a couple years back now, i.e., compact double cranks with semi wide-range rear cassette... and more recently, wider-range cassettes with the aide of the K-Edge extra-long rear derailleur cage. 48/32 is a bit odd vs. 50/36 or 50/34. Same system Calfee, Paketa, Eriksen and other high-end customs have also been fielding.

Took me about a day and a half to get my timing down for the way Di2 shifts and found that I had to double shift a lot, which is the norm for compact doubles even on a single bike. It was nice, but didn't strike me as revolutionary. Battery life didn't seem to be an issue either, noting a full-charge would deliver something like 2,000 shifts and your battery indicator gave you plenty of advanced notice as to when a charge was required.

It seems to me that when using the mid range of gears a compact double requires a lot of cross chaining and double shifting. Unfortunately the mid range is where most people spend most of the time. I would rather have a triple that allows most of the time spent in the mid range to be spent in the middle ring which minimizes double shifts. Maybe someday we will get an electric triple.

I have had Ultegra Di2 on my single for a few months.
My main reason for getting it was a hand injury and I thought it would also improve shifting.
For the most part it does shift smoother than mechanical, but on certain cogs it does make some noise.
Surprisingly, I miss the feedback you get with a Campy mechanical shifter, you push a button and then after a slight delay it shifts.
I don't like the shape of the Shimano shifters, much prefer Campy.
I am going to try reverse Engineering the buttons and make my own version with Campy shifters.
Another advantage is not worrying about breaking a shift cable, fewer and easier adjustments and it makes the bike look nicer and easier to clean.
I don't think I would like the big jumps with an 11-34 cassette so wouldn't consider it unless they come out with a triple.

I have had Ultegra Di2 on my single for a few months.
My main reason for getting it was a hand injury and I thought it would also improve shifting.
For the most part it does shift smoother than mechanical, but on certain cogs it does make some noise.
Surprisingly, I miss the feedback you get with a Campy mechanical shifter, you push a button and then after a slight delay it shifts.
I don't like the shape of the Shimano shifters, much prefer Campy.
I am going to try reverse Engineering the buttons and make my own version with Campy shifters.
Another advantage is not worrying about breaking a shift cable, fewer and easier adjustments and it makes the bike look nicer and easier to clean.
I don't think I would like the big jumps with an 11-34 cassette so wouldn't consider it unless they come out with a triple.


Campy Electronic an option?

Chris W:
Using our FSA Carbon Pro Team triple crankset we had on our Zona.
Rings were changed as follows:
Inner ring: FSA 32T.
Middle ring: FSA 48T.
Outer rim: FSA 42T 'toothless' ( 42T ring with teeth removed).

Tandemgeek:
NMH battery and it's setup is the diffference + ease of recharge when needed.
Improvements to systems are done in increments. Big changes from downtube shifters on our Follis tandem back in 1975 . . . all these little changes add up don't they?
Heck, the NMH rechargeable battery may outlive both of us!
While 48/32 may seem a bit odd, it's what we specified.
We've specified other 'odd' things on our tandems before!

Wayne:
We too spent most of our time on middle chainring on triples. Inner ring was for steeper climbs only. Large ring for going down the same hill and tailwinds.
With our new setup we spent most time on the 'big' 48T ring.
For bit of hillwork we can drop down to the 32.
We have adopted quickly/easily to the new gearing arrangement.
Pilot always called out all shifts for stoker when we had triples.
Now she asks me to call out front der. shifts only.
With 3x9 system only about 20/22 usable gears.
With the 2x10 setup we have 20 usable gears; the automatic adjusting of the electronic front der. allows proper chain alignment. No trimming for chainrub. That had been our issue with STI.
The ultrasmooth/instantaneous shifting is easy to get used to.

For triple lovers, Shimano could come out with Di-3 . . . but don't hold your breath!

Pedal on TWOgether!
Rudy and Kay/zonatandem

Great "first peek". Look forward to future reports.

Looks like Bob Davis and Craig Calfee were a bit ahead of the curve.
Shimano just announced new Di2 11-speed with . . . . new battery set-up in seatpost!

Stoker and I are are doomed forever to labor with mechanical shifting:( We've got a 24-36 low now and need every bit of that to get up 15% grades even for a moderate distance. Since I'm retiring in this same area I don't see much cushy, flat tandem riding in our future. Darn.

Rudy,
You and stoker Kay being test dummies is a win/win all around. You get new gear, the company has limited exposure;)

With the 2x10 setup we have 20 usable gears; the automatic adjusting of the electronic front der. allows proper chain alignment. No trimming for chainrub. That had been our issue with STI.


Pedal on TWOgether!
Rudy and Kay/zonatandem

Evidently the STI system has received some updates as we do not have the issue you describe. We are using 6703 shifters with DA dr with Ultegra cranks and the system works exceptionally well. No electronic shifting in our near future.

Wayne

DubT and Tomki:
Our D/A STI was one of the earlier types, and as with everything else, as issues develop sometimes they get
rectified in the next model update.
Have used mechanical shifting for decades, from downtube to barcons, to indexed and STI . . .all worked; some better than others.
The Di-2 with new battery setup offer by Bob Davis to test was just too good to pass up!
Shimano just announced upgraded Di-2 for 11 speed and battery in seatpost (Copycats?!) there is yet another choice; that is until Campy or SRAM
come in with a system of their own, which is quite likely.
Pedal on TWOgether!
Rudy and Kay/zonatandem

We've got 300+ miles on the Di-2/new internal battery system we have been testing.
Di-2 works great, as advertised; easy to get spoiled on that setup!
Battery still at top level charge according to the voltage meter.
Currently riding in northern Utah to get away from Tucson's 100+ temperatures; at least 20/30-some degrees cooler here with low humidity (10% today).
Nights still get cold enough to sleep with a blanket and the heat on!
Love it!
Pedal on TWOgether!
Rudy and Kay/zonatandem

What happens if the battery or electronics fail? I know stuff gets more and more reliable but we still support 4.5 people through repairing failed electronic apparatus. Is there a mechanical, get-you-home, fallback?

Mugre

Alas, we couldn't live with "only" a 32-34 low gear with the climbs we have to do and a 48-11 wouldn't be tall enough for our downhills. I wish the Earth were flat, but it ain't so. No matter, I'm sure Shimano will come out any day now with a user-programmable model that we can adapt to our daVinci quad chain rings;)

Alas, we couldn't live with "only" a 32-34 low gear with the climbs we have to do and a 48-11 wouldn't be tall enough for our downhills. I wish the Earth were flat, but it ain't so. No matter, I'm sure Shimano will come out any day now with a user-programmable model that we can adapt to our daVinci quad chain rings;)

I think the user programmable model is planned for release the year after the triple version.

We are riding the ultegra di2 on our Calfee tetra- we have the 11-34 cassette and 50/34 compact from praxis up front- those ratios have given us all the hill climbing we have needed- shifts are crisp, quiet and very smooth even under tension. Derailer adjustments with di2 are also pretty effortless from the junction. No chain drops either.

An aside- we have charged our battery once -before our local tour de cure- rode the metric. Century and another hundred or so miles after. This Sunday shortly into our ride, shifting become intermittently responsive before ceasing. Troubleshooting identified that I had not securely screwed the cable for the battery into the seatpost battery. The cable had fallen down the stokers seat tube and was unreachable. Fortunately with the 28 pound bike, I was able to hold it upside down, overhead and shake the cable where my wife could grab it. Sadly it was on a very isolated road and there were no drive by witnesses.

If electronics/battery fail completely then you are stuck in what ever your last gear selection was.
However, there is a 'low battery' indicator light system that warns you when battery is at 50%, another when at 25%, another at 0%.
Idiot/warning lights are green and red; as charge diminishes down to 50% green light flashes 5 times; red flashing at 25% and 5 red flashes when down to zero. Should get your attention.
With the new battery system we are currently testing NiMH/LSD (Nickel Metal Hydryde/Low Self Discharge) compared to Shimanos Lithium Ion battery we can access/recharge the unit with wire connector out of top of stoker's seatpost. To recharge plug into electric outlet.
For testing ppurposes we are also taking voltage readings before and after each ride. Those connections are also under stoker's saddle.
As for the question 'what happens if all fails with the electronics?'
What happens if you break non-electronic derailleurs/cables?
Been there, done that . . .
So far we are impressed; voltage readings are high and no flashing/warning lights so far.
Heard rumors of possible Di for triples, but nothing official.
Improvements will happen as shown with Shim's newest Dura Ace 11-speed system, the battery is no longer located externally.

Shimano and Fox are cooperating on a system for electronically controlled shocks and forks . . .
Seems electronic applications for bicycles is the latest trend.
As more companies explore electronics, prices are sure to be less wallet busting!
Pedal on TWOgether!
Rudy and Kay/zonatandem

Update on "Test Dummies" Di-2 NiMH/LSD battery system:
So far have 750+ miles on this system.
No real issues; 99.99% reliable.
Have not yet had to recharge the battery.
Minor issues:
Noise at rear derailleur; nylon string caught/rapped into cassette.
A couple of 'overshifts' when going to big (48T) chainring. Chain went over/derailed onto the the outer 42T (toothless) chainring and able to shift it back to 48T easily.
System would not shift at all; checked out the electronic connectors; the connection to the junction box by the handlebar had become loose somehow. Reconnected it and all was fine again.
So far still impressed . . . after 37+ years of tandeming TWOgether, we are not easily impressed!
Pedal on!
Rudy and Kay/zonatandem