DubT

Our Calfee Tetra is 5 years old today. In that 5 years we have ridden it 29,000 miles in Illinois, Indiana, Michigan, Wisconsin, Tennessee, Florida, Texas and Oklahoma.

It has received several updates: Cranks, Gates belt drive, Wheels, Saddles, Handlebars, Stoker Seatpost, Pedals, Water bottle cages and the Stoker stem. I also reduced the rear wheel spacing from 145 to 132.

We are still thrilled with the bike! The current plan is to ride it another 5 years and then see what the market is doing. I have resisted updating to 11 speed and electronic shifting, maybe someday in the future.

The two big issues have been saddles and wheels, it took several attempts to find saddles that we were both comfortable with (we are both using John Cobb saddles) and 4 sets of wheels before I was satisfied.

Here are pictures from 5 years ago and from today.

oldacura

Beautiful bike. I can't tell if you're running a triple chainring. If so and if you like or require the range that affords you I would resist the temptation to go electronic.

If you like a narrow gear range, electronic is pretty nice. If you want a wide range, I'd stick with mechanical.

DubT

We are running a triple 30-39-52 with a 12-30 cassette. I am VERY happy with the gearing and do not want to screw it up. That is one of the main reasons that I am still mechanical. I also have spare mechanical parts and have gotten pretty good at adjusting for good shifting.

oldacura

Our older bike has 54/44/30 with an 11-34 cassette. The low gearing is necessary for climbing steep hills. The 54x11 is a blast when we get to pedal downhill. The new bike is setup for 34x36 low and 52x11 high with big jumps. This is stretching the limits.

twocicle

We concur about the 11-36 (SRAM) 11spd cassette ratio jumps. Even though we run a 48t front ring, our cadence can change by some 12-15rpm on many of the mid to small cogs. The 36t rear cog is great for spinning up >10% climbs (with our 30t granny), but otherwise we much prefer using the Shimano 11-32, or 11-28 cassettes.

Our 48/30 double chainrings with a 11t small cog (11spd cassette) affords the same ratio range as Wayne's triple chainring w/10spd cassette but with fewer overlap gears, so we are not missing anything by using a double Di2 11spd setup.

That said, I am still contemplating whatever triple Di2 options may be available in order to have a bigger front spread and tighter rear cogs, while providing that oh so easy 30x36t ratio (or equivalent).

Wayne, nice Pi bars! lol. The rest of the bike isn't bad either

oldacura

Seems like Shimano is out to kill front derailleurs. Most new mountain bikes are 1x11. I can see how complete elimination of the FD has its advantages. However, I don't really see many advantages of a 2x over a 3x. I'm sure that most racers have no need for a 3x (but I'm not a racer and don't pretend to be). Simply adding a 3rd position for the derailleur doesn't seem that difficult.

I understand that 3x XTR Di2 is available but won't work with road shifters. Is the prospect of a 3x road Di2 more than a rumor?

DubT

Thanks, I really like the bars, they are EXTREMELY comfortable and offer a variety of hand position. Also Thanks!

LastKraftWagen

Actually, the last I read the XTR triple would work with the road levers, but it won't work with the DA or Ultegra RD, and the arc of the FD doesn't work well with the typical road rings. Won't swear to it- I haven't looked at any DI2 info in a while.

twocicle

Not to digress into another Di2 discussion, but yes, the XTR fd/rd will work with road e-tube shifters. I was referring more to the XTR chainring spread limitiations. Plus as Turbotandem pointed out, the fd triple inward limit is setup for a mtn chainline, which can pose a problem for narrow Q road cranks.

twocicle

To reiterate, 3x XTR Di2 is available and DOES work with road E-TUBE shifters. Turbotandem also reported that SYNCRO shifting does work, contrary to what Lennard Zinn had relayed from Shimano.

It was all discussed here: https://www.bikeforums.net/tandem-cyc...m-project.html

mtseymour

Nice setup! We're only on year 2 but have also gone through our share of component changes. It's been a fun journey.

Why did you go from 145 to 132 rear spacing? How difficult was the frame modification?

What made you go through 4 set of wheels before settling on the HED?

mtseymour

Shimano is only responding to market demand. My guess is that Shimano launched XTR Di2 to slow the huge shift to Sram's 1x11 drivetrain among mtn bikers. Unless you're an elite racer, it makes more sense to ride Di2 with 1x11 than 3x11.

For most road riders, the 28T and 32T cassette have made the granny obsolete. It's uncommon to see a road triple on a century ride or Gran Fondo. With spin classes becoming more popular (incl the use of Powermeters), it's now easier to learn to spin more efficiently and at higher cadences (90 rpm+). This makes it practical to use 50-34 or 52-36 cranks.

I suspect that we'll see a lower-price Di2 (ie. Di2 105 or Sram Force eTap) before we see Di2 road triple.

Trsnrtr

Nice looking ride, Wayne.

DubT

I will start off saying that I have been a big fan of HED3 wheels for years and those are the wheels that I wanted on the bike when we built it. However i was convinced to go with 145mm rear spacing which ruled them out. I bought a set of Bontrager wheels from Mel at Tandems East to get some tandem specific wheels at a decent price. They were extremely heavy, then based on TG's report about the Topolonio wheels I bought a set of them (against his recommendation) They were very light and comfortable. They started developing rim cracks so I bought a set of Spynergy wheels from Mel. Because of a derailleur getting into a wheel and bending the rear hanger I modified the rear hanger to become a bolt on. At that time I recognized that adding a spacer on either side or the rear drops would allow me to reduce the overall rear spacing and then use a standard 130/132 spaced rear wheel. I bought two new drops from Calfee and bolted them in as spacers. Easy conversion and accomplished the desired result. I now have HED3 wheels on the tandem and on my single.

So long story short do a lot of research before specing wheels. I still have the Bontragers and the Topolinos but sold the Spynergy's.

LastKraftWagen

Sorry, my comment was menat in reference to an earlier post regarding the compatibility of DI2 road levers and XTR derailleurs.

oldacura

The Gravel tandem project says that they use XTR Di2 with a 44t x 10t high end but this is lower than we want.

akexpress 

Santana has reported success using a normal triple road chain ring setup with xtr di2 derailleurs and road levers by fabricating a angled washer to kick up the rear cage of the front derailleur to accommodate the big chain rings

bwebel

Do you have any issues with the derailleur having the range to shift all the way to the inside? Could you post a closeup of the rear triangle? I'd love to put trispokes on our Calfee. Would it be possible to relatively easily move from 145 to 130 spacing with your setup?

thanks,

DubT

Here is a link with pictures. https://www.bikeforums.net/tandem-cyc...ront-rear.html

jnbrown

Here is ours also about 5 years old.
Changes since I first built it up:
Rebuilt wheels with wider, deeper alloy rims.
New stem and bar for stoker.
Body float seat post for stoker.
SMP saddle for me and Selle Itailia Diva saddle for her.
Changed rear shifting from hybrid Campy / SRAM to all SRAM using SRAM Red shifter.
Recently discovered both chains where worn out, replaced both with KMC, couldn't believe how much smoother the drive train is now.
The KMC X10SL on the back definitely shifts better than the old Ultegra 10 speed chain.
We absolutely love the bike, the ride is amazing.