Tandem Cycling - my Calfee Tetra build

We recently sold our previous tandem due to stoker fit issues and thought we might just build up a lower cost "beater" this time around and not go overboard. Then my stoker happen to stumble upon a new 2007 Calfee frame for sale from a dealer near Sacramento, CA... and the semi-hi tech/bling game was afoot again. This was such an unusual find we can't believe how lucky we were to get this perfect fit - a medium/small and the added option of a 2cm headtube extension (reduces steerer stack height which nets in a stiffer front end).

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Here is the intended list of dodads for this new tandem. A few functional items are duplicates (cassettes & brakes) to allow swapping as needed. The initial build/workstand photos show a temporary stem and seatpost just put there to hold the frame and fork in place until the final steerer tube height is determined.


2007 Calfee Medium/Small Tetra. 145mm rear spacing
Alpha Q fork paint matched. 700c 44mm rake.
Cobalt Blue Opaque w/Horizontal fade

SHIMANO
---------
Ultegra:
R601 175mm Captains crankset, w/BB6700 68mm
R603 170mm Stokers crankset, w/BB6700 68mm 52/39/30 rings
6700 Brake calipers (rear caliper TBI due to Avid BB7 installed on rear)
6703 10-Spd triple (3x10) shifters
6703 front triple derailleur
6700 11-28 cassette
6600 10-Spd chain for drive side (SRAM PC 1051 created problems with the big chainring pins)

XTR M972 SGS rear derailleur
XT M771 11-34 cassette (wider range for steeper hill climbing. not typically req'd for our general riding)
XT RT86 IceTech 203mm 6-bolt Rotor (a great replacement for Avid rotors)

OTHER
---------
Chris King NoThreadset (headset)
Spinergy Tx2 tandem wheels w/rear disc
Continental 4-Season 25mm tires

Avid BB7 rear disc caliper w/203mm IS adapter
Sram PC 991 (9spd chain) + KMC 3/32" half-link - timing side.

Jagwire Racer Road Complete Brake and Derailleur Cable & Housing Kit
Jagwire Hyper Slick Stainless tandem length cables
Jagwire in-line cable adjusters
Cinelli cork handlebar tape
Frame-saver tape: ISC Helicopter-OG Surface Guard Tape (8 mil Outdoor Grade)

Ritchey WCS EVO Curve 31.8mm 42cm drop bars - captain & stoker
3T ARX stem - captain 120mm 6 degree
3T ARX 31.8 stem - stoker 140mm 17degree
Deda Elementi Zero100 seatposts 27.2mm
Terry Zero Ti Captain, Terry Butterfly Ti - stoker
Speedplay Zero pedals - captain (stainless) & stoker (Ti)
Cane Creek stoker pegs
Arundel Sideloader carbon bottle cages (3)
Lezyne Carbon bottle cage w/integrated pump holder (1)
Lezyne Road Drive pump

Computer(s):
Garmin Edge 800 (dual for both capt & stoker), with a single Spd&Cad Sensor
FSA Control Center mounts (2)


As you can see from the list above, I made a conscious decision to go alloy on the handlebars, stems and seatposts. The selection is still very lightweight but also durable and a lot more cost effective. Besides, I wanted to avoid problems attaching a seatpost rack on the back, aero bars on the front, and never liked the idea of having a stoker stem clamped on a carbon captain seatpost. With the carbon Calfee frame and AlphaQ fork, plus the Spinergy wheels, the ride should be plenty plush without needing the upper accessories to be carbon as well.

Starting with getting the Chris King headset installed at the local bike shop. Don't freak out about the photos showing the brake pads not lining up... it's a build work in progress.


Update: Full completed build web album:
https://picasaweb.google.com/109550774138928798662/OurCalfeeBuildupPics?authuser=0&authkey=Gv1sRgCJn3h_-3nd7BYA&feat=directlink

https://lh6.googleusercontent.com/-nVfdlyPwDzI/T5CZtRj8LyI/AAAAAAAAAD4/wCQQRwAheG8/s800/P1010448.JPG

https://lh6.googleusercontent.com/-hxVb5vQ5XQI/T5CZwV4sMuI/AAAAAAAAAEY/K93J91HBGfg/s800/P1010453.JPG

https://lh3.googleusercontent.com/-CysLkmVxIxs/T5CZ1uIUrCI/AAAAAAAAAFI/Yiwc5uIM1Do/s800/P1010460.JPG

https://lh6.googleusercontent.com/-7M5XN427ljo/T5CZ2ZvgWoI/AAAAAAAAAFQ/1hN7SgeIPfg/s800/P1010461.JPG

https://lh3.googleusercontent.com/-OJSq5JHnwKw/T5CZ0l94qbI/AAAAAAAAAFA/B0BjEqm27u8/s800/P1010459.JPG

https://lh4.googleusercontent.com/-nczWNrUpzUw/T5CZ3oidhCI/AAAAAAAAAFg/tt-ZKod22bA/s800/P1010463.JPG

https://lh6.googleusercontent.com/-7vW3egUrRyk/T5CZyLPRA2I/AAAAAAAAAEo/093Fzp-svrs/s800/P1010456.JPG

https://lh4.googleusercontent.com/-YRVHTmoUcJw/T5CZ6m_pYGI/AAAAAAAAAGA/AuE1uYDkc7w/s800/P1010467.JPG

https://lh3.googleusercontent.com/-UbWk8glz-Aw/T5CZ5BM6PLI/AAAAAAAAAFw/7rycAiq94v4/s800/P1010465.JPG

Looking good!

You may want to replace the Calfee eccentric with a Bushnell if it will fit that vintage frame. Tandemgeek converted his from the Calffe to the Bushnell and based on his experience that is how we speced our frame.

Very nice color.

You may want to replace the Calfee eccentric with a Bushnell if it will fit that vintage frame. Tandemgeek converted his from the Calffe to the Bushnell and based on his experience that is how we speced our frame.

I could be wrong, but from the photos it looks like it has the larger Calfee eccentric, which would mean the Bushnell eccentric would fit. If the eccentric has an aluminum sleeve, then it is the "new" specification. If so, the OEM Calfee eccentric will probably be OK with this build given the use of the BB6700 bottom brackets.

Mine use of the Calfee eccentric was problematic because I still use older style square taper bottom brackets that pushed outward against the Calfee eccentric halves. The newer BB's and cranks like the BB6700's don't do that.

All that said, if the frame has the larger eccentric with the aluminum sleeve then the Bushnell would always be an option if it was ever wanted or needed.

Thanks guys. Yes I had read Mark's blog saga of the eccentric, but beggars can't bee choosers.

This 2007 model predates the design change, but for a measly $500 Calfee will ream it out to accept the larger/current eccentric. That and the frame shipping fee would be a killer. We'll try to live with it as most(?) pre-08 owners have. Sadly, the eccentric bolts are indeed slightly buried under the edges of the BB6700 rim. I have some ball-end hex wrenches coming.

One other design change on newer models is a little more room for the 203mm disc rotor on the new frames. I did a mock-up test with the Spinergy Tx2 wheels and had maybe 2mm to spare between the rotor and chainstay.

I've already made a mental note about a couple things I would have done differently: 1) opted for a navy blue Chris King headset, and 2) white spoke wheels.

Anyone know if it is possible to safely remove decals? This frame has a few more than we prefer. If so, how?

I actually added a couple of decals. I believe they are put on and then clear coated. Removing them would probably screw up the finish.

As for the eccentric, when we were specing ours, Michael at Calfee, asked if I ever intended to use a belt drive and I told him that I may in the future, he said that the Calfee eccentric was more difficult to install square and could cause problems with a belt drive system. You may want to give Calfee a call and get more details. The new CDX drive that is supposed to be available this winter may be the answer.

It is a great looking bike. I think you made the right choice with the black spokes too. The black headset is probably best as well as a blue one is bound to be a different shade from the blue on the frame so may not look as good.

I actually added a couple of decals. I believe they are put on and then clear coated. Removing them would probably screw up the finish.

As for the eccentric, when we were specing ours, Michael at Calfee, asked if I ever intended to use a belt drive and I told him that I may in the future, he said that the Calfee eccentric was more difficult to install square and could cause problems with a belt drive system. You may want to give Calfee a call and get more details. The new CDX drive that is supposed to be available this winter may be the answer.

We'll see about the belt drive once those parts arrive (backordered). The frame was designated as "belt compatible" by Calfee on the original build sheet. I assumed there would be some fudge factor by using a spacer on either the front or back between a timing crank and the BB.

I think maybe I was a bit gun shy from Santana decals on the prev bike. Those scuffed off and otherwise looked shabby very easily. Bill actually told me that they could not clearcoat over their decals as that would void the Dupont paint warranty. These Calfee decals do seem to be glazed over so they should be more durable.

Yes, the semi-transparent lower paint is really cool. Would love to have a frame with 80% done like that.

Ok, I got the replacement set of Shimano Ultegra FC-R603 rear cranks today and installed them. A first time installing this style timing-side crankarm which is similar to a XTR M970. After installing it I found out that to remove the arm needs a rather expensive ($38) TL-FC35 tool :(

I also learned that there is no preload adjustment on these cranks. I guess that is similar to FSA cranks that only use spacers to take up any slack between the bottom brackets and crank arms? I ended up with just the washer/spacer on the timing crank side, and added both a .6mm + .1mm spacer on the drive side. This was the amount of spacers determined by the tester tool Shimano provides. The end result seems to align the front and rear timing rings to roughly within 1mm (quickly measured from the seat tubes outward). I'm stuck with the rear crank setup for a few days until the TL-FC35 tool order comes in.

One other slight gripe about these cranks is the open hex hole end in the timing crank bolt. That provides a nice entry point for grime & water access to the inside the axle. For peace of mind, I'll have to devise a rubber plug and/or silicone blob to seal that (BTW, this is the same type of cruddy design that the XTR M970 has... with the open-ended crank bolt).

Good news about Q-Factor. I measured (rough) 150mm on the front/captain, and 159mm on the rear/stoker. My wife is really happy to hear that about her cockpit, as it's only 4mm wider than her road single w/triple. Our previous Santana had her at a tripod stance of 172mm which is really tough on a 5'2" stoker. Heel clearance is now identical to her single at 2.5cm, unlike the Santana which had 1cm less. So things are looking really good for biomech leg setup.

Glad to hear you're coming around on the decals. I think they look good, and won't look so prominent once you have all the components on the bike. Plus, with quality frames like that, it's fun to see them 10 or 20 years down the road still in the original format from the factory.

The paintjob is gorgeous. Maybe if you had a couple particular spots that you scraped on your Santana, and think you will again on that Calfee, you can put some clear protective tape on it beforehand.

Good news about Q-Factor. I measured (rough) 150mm on the front/captain, and 159mm on the rear/stoker. My wife is really happy to hear that about her cockpit, as it's only 4mm wider than her road single w/triple. Our previous Santana had her at a tripod stance of 172mm which is really tough on a 5'2" stoker. Heel clearance is now identical to her single at 2.5cm, unlike the Santana which had 1cm less. So things are looking really good for biomech leg setup.

The Santana stock Ultrgra cranks that I have worked with have had a wider Q factor than needed due to a very long BB. I replaced old style Ultegras and long bottom bracket with daVinci cranks and 113mm square taper BB and get 164mm Q factor on both an Arriva and Noventa. Probably could go a few mm narrower if needed.

The Santana stock Ultrgra cranks that I have worked with have had a wider Q factor than needed due to a very long BB. I replaced old style Ultegras and long bottom bracket with daVinci cranks and 113mm square taper BB and get 164mm Q factor on both an Arriva and Noventa. Probably could go a few mm narrower if needed.

Right. Sometimes that is a doable option.

However we had a Sovereign (AL) which has larger tubing than your Arriva and Noventa, plus the typical 160mm rear spacing. The crank arms were already very close to the chainstays so there wasn't any room to move them closer by using a shorter spindle or different cranks. That was a dead end for us. Having a sub-160mm Q on this new tandem is an enormous benefit for her setup needs.

On the front, these Ultegra captains cranks at a Q of 150mm are only 3mm wider than the Dura Ace double cranks on my single.

I glad you could get the lower Q factor that you needed. To me the ability to get a proper fit is the most important feature of any bike.

I always wondered why Santana made the Q on their steel tandems wider than needed. I suppose it lowers production costs a small amount to use the same BB width on all the tandems even though the steel ones could use a more normal setup. Then again if they did that it would be admitting that some like or need a narrower or even wider setup.....

I glad you could get the lower Q factor that you needed. To me the ability to get a proper fit is the most important feature of any bike.

I always wondered why Santana made the Q on their steel tandems wider than needed. I suppose it lowers production costs a small amount to use the same BB width on all the tandems even though the steel ones could use a more normal setup. Then again if they did that it would be admitting that some like or need a narrower or even wider setup.....

Santana's extra wide Q is due solely to the alignment needs (ie: chainline and chainstay clearance) created from their 160mm rear wheel spacing - touting the latter as a "stronger" wheel, at the peril of exceeding any and all other Q ranges. It works for those lucky enough to be able to accomodate the very wide stance, but there are many smaller stature stokers who are at the other end of the spectrum for whom it doesn't work - or works up to the point where severe damage is done to the knee joints as a result <- ie: what happened to my stoker.

Santana's extra wide Q is due solely to the alignment needs (ie: chainline and chainstay clearance) created from their 160mm rear wheel spacing - touting the latter as a "stronger" wheel, at the peril of exceeding any and all other Q ranges. It works for those lucky enough to be able to accomodate the very wide stance, but there are many smaller stature stokers who are at the other end of the spectrum for whom it doesn't work - or works up to the point where severe damage is done to the knee joints as a result <- ie: what happened to my stoker.

I have read that countless times. I also know that Santana claims that Q does not matter.

I firmly believe that Q factor is very important to some people including my stoker. So I am very much in agreement with you there. My stoker needs a very wide Q but I understand the need for proper alignment either narrow or wide.

It seems to me though that the stock crankset carried by Santana and installed on all its tandems is wider than needed on the steel models. It appears that they designed a crankset that works on their popular aluminum tandems with wider chainstays and use it on the steel ones as well.

My steel tandems work well with cranks at 165mm Q. Chain line is fine. Shifting is fine front and rear. I suppose using one standard BB allows them to carry less inventory and support their customers with stock cranks but it means all customers are stuck with the wider Q factor.

Back to the build up of this Tetra, looks like we'll be able to hit close to 27lbs and that is with the Avid disc installed, pedals and all! Big smile.

As a preliminary weight sample, yesterday I piled on 3 full lengths of SRAM chain, an entire cable package (uncut wires & housings), an extra temp stem holding the forks in place, and our biggest XT cassette... came to 28.2lbs. Knocking off the timing chains in leau of carbon belt, the extra stem, and swapping out the steel disc rotor for the Shimano ICE rotor, should help drop about a pound.

Sounds good, what are you waiting on in order to finish the build?

After receiving the stems and seatposts we finally had a chance to confirm the height & reach requirements with the final components. Frame is now back at the shop for the AlphaQ steerer cut and glue in the plug for the top cap. I'm leaving just under 7cm total steerer tube above the headset. The captain stem clamp is 4cm tall + 2.5cm of spacers under the stem, and one 5mm spacer above (some carbon steerer left above the stem for tube strength).

I'm a few days behind in the project from where I wanted to be. The Deda Zero100 seatposts required a little extra work to get the stoker stem clamp up at the correct height. It wasn't until installing that I found the seatpost started to flare wider at the top, just where the stoker stem was going to clamp. Since the 3T stem basically has 2 independent clamp bands, I ended up using a half shim just for the lower stem clamp bolt. Seems to hold very well.

I think our only other option would be to revert to the typical adjustable stoker stem (at 372gms) is a bit of a brick. Those usually have a 35 degree clamp and would attach lower on the captains post, avoiding the flared part. Unless anyone knows where to get a fixed stem with that increased clamp angle (and would match the reach length of our current 140mm 17 degree)?

Calfee is currently not producing their adjustable carbon stem, but they plan to in the near future. Maybe we'll just wait for that and use the 3T for now.

What's the seatpost diameter?

PK

Seatposts are 27.2. Of course most stems available these days require a shim up to at least 28.6 (1 1/8). 31.8 handlebar clamp.

It's coming along. Cable routing done and ready to wrap (excuse the ugly temp tape job). Bummer... re-weighed with everything installed and came to 29lbs. Somehow it gained weight since my last measure. Chalk it up to bad math the last time round. This is with pedals, Avid disc, waterbottle cages... stuff that normally isn't included by the mfr. You could probably chop off 1.5lbs for those components, so comparing apples to apples we're looking at a 27.5lb "advertised" build. Ridable weight of 29lbs.

Maybe the guys at the bike shop are playing a joke on us and dumped some lead weight in the seat tubes ;)

Have you measured the length of the boom tube, from center-to-center between the two bottom brackets? If not, you might want to check that to make sure just how long that stoker compartment is. As noted in your other thread on the belt, I'm thinking you've got something less than 28.5". You can usually double check the length at the seat tubes since many tandems tend to use parallel seat tube geometry, e.g., 73° front & rear, and I think Calfee's fall into that category unless they are for either very short or very tall teams.

This standard Medium/Small frame is suppose to be 72cm stoker top tube, with identical 74 degree stoker/captain seat tubes. That also confirms my measurement of the bottom tube center-center BB of 72cm since the parallelogram format dictates the bottom length will be the same - barring some funky BB offset by the builder.

Mark Johnson has the geometry posted here: http://www.precisiontandems.com/cat_files/calfeecolor&geometry.htm

That also confirms my measurement of the bottom tube center-center BB of 72cm since the parallelogram format dictates the bottom length will be the same - barring some funky BB offset by the builder.

The first generation Gates Carbon Drives for tandems used 71t sprockets, and that's probably what you need.

Co-Motion worked with Gates to develop the tandem sync drive and the 71t rings that Gates spec'd for their 724mm (28.5") stoker compartments / boom tubes made for a VERY tight fit. Gates came out with the 69t sprockets as a system "enhancement" to address the tight fit on Co-Motion's tandems.

FWIW, Co-Motion published their own FAQ for the Gates system and it's worth a read for anyone who is doing the Gates upgrade on their own:'
http://www.co-motion.com/index.php/information/faqs/the_gates_carbon_drive_timing_belt_system

So, are you using the 11-28 or 11-34 cassette?
Currently my tandem is experiencing the chain length, rear derailleur capacity issue.

So, are you using the 11-28 or 11-34 cassette?
Currently my tandem is experiencing the chain length, rear derailleur capacity issue.

I have the XT 11-34 cassette installed right now in order to properly size the chain length and tune the derailleur jockey positions. To start I used the method of big cog -to- big chainring + 2 links (without running the chain through the derailleur). That was just minus 2 links on the Sram PC 1051 P-Lock 10-Speed chain OOTB.

The XTR M972 SGS rear derailleur has the capacity to handle the max 34 sprocket size on the back plus the total tooth diff count which includes the chainring sizes (52-30 = 22) + (34-11=23) = 45 total tooth diff. It is running the small to small without chain slap, and can still handle the big to big (never used deliberately IRL but you have to allow for it so as to not completely trash your derailleur by mistake).

So the XTR M972 SGS is 9spd rear derailleur right?

I'm having a difficult time when using the BIG Chainring and shift to a biggest cog. I'm thinking to change a smaller size cassette or adding more links to the chain.
I'm currently using M771 or 772 RD with 112Link 10spd chain.

So the XTR M972 SGS is 9spd rear derailleur right?

I'm having a difficult time when using the BIG Chainring and shift to a biggest cog. I'm thinking to change a smaller size cassette or adding more links to the chain.
I'm currently using M771 or 772 RD with 112Link 10spd chain.

Correct, the XTR M972 is the same spec as the XT M772... both are classified as 9spd derailleurs. However, the throw ratio is perfectly fine for these to work with 10spd cassettes too. You did not mention if you have the GS or SGS M7nn series. If you also have a 34 cog on the back, then you need the SGS (super long cage).

Otherwise, your problem could be a number of things including chain length, jockey wheel distance, alignment, preload tension.

Correct, the XTR M972 is the same spec as the XT M772... both are classified as 9spd derailleurs. However, the throw ratio is perfectly fine for these to work with 10spd cassettes too. You did not mention if you have the GS or SGS M7nn series. If you also have a 34 cog on the back, then you need the SGS (super long cage).

Otherwise, your problem could be a number of things including chain length, jockey wheel distance, alignment, preload tension.

Thank you so much for answering!! :)
https://lh5.googleusercontent.com/-k93KRzDC0Q8/T44QkjLfkeI/AAAAAAAACMY/4y70e4gQSog/s922/P1070116+-+Copy.JPG

As shown on the picture. Current the chain is on middle chainring and biggest 32t cog.
I just checked back the purchase history, it's "SRAM PG 1070 Cassette 11/32t". If I shifted to biggest ring, it will stretch to the red line position. For most of the time it just struck and could shift.

Should it be the chain problem? I'm using KMC 114L 10spd chain + 10spd shifters.

Thanks :))!

Yes, chain is too short to allow for big-to-big.

One of the more consistent methods to determine the correct length is to run the chain from big cog-to-big chainring without running the chain through the derailleur, get the chain tight and align to the next whole link configuration, then add 2 links (needed for jockey wheel routing). Then go install the chain through the derailleur for normal use.

Adjust the derailleur tension screw just to the point where the chain is not slapping the chainstay when running in the small-small sprockets. Increasing the derailleur's pull to the rear will increase the tension on the chain, but don't go too far as this descreases the amount of chain wrap around the rear sprockets. Depending on the status of your derailleur springs, you may not be able to develop enough derailleur tension to keep from chain slap in the small-small. but then you shouldn't be riding in that combination anyway.

I took a first solo spin this afternoon around the block a couple times for a quick checkout ride. Handles very nice, light feel, quick and nimble steering. All the shifting and braking worked great, so those components are all good. Sweet! :) :)

I may consider installing cable liner along the top tubes as the rear brake wire run sticks out more to the side than under, and it may prove bothersome having the bare wire there rubbing legs, tights, etc.

Other todo: replace the 130mm captain stem with a 120mm (in transit). The eccentric orientation with a tight timing chain is now in the 7 o'clock position which is somewhat further back than I anticipated. Adding 2 links is not possible as the eccentric does not have enough uptake to tighten the chain. This setup will now require moving my capt saddle back approx 1 cm and hence the shorter stem.

Adding 2 links is not possible as the eccentric does not have enough uptake to tighten the chain. This setup will now require moving my capt saddle back approx 1 cm and hence the shorter stem.

I've successfully used 3/32" half-links on our tandem's sync chains to solve similar set-back issues. It's not a perfect match to 9-speed chains, but since the sync chain is a direct drive it doesn't really matter.

I've successfully used 3/32" half-links on our tandem's sync chains to solve similar set-back issues. It's not a perfect match to 9-speed chains, but since the sync chain is a direct drive it doesn't really matter.

Super! Thanks for the tip, I never thought of that. Duh.

Using a couple of these links seems a much better option than an entire (and very heavy) half-link chain. These just might work to keep the chain short enough to let the eccentric work in the forward, 4-5 o'clock position: http://harriscyclery.net/itemdetails.cfm?ID=1274

Now, for the timing chain I am using a Sram PC 1051 P-Lock 10-Speed chain. In the past I found that using non-straight links (ie: not BMX style) seemed to track a lot better, so I currently use the same Sram PC1051 on drive a timing. Do these 3/32" 1/2 links work alright with this type of chain (10spd) or do I need a 9spd chain, and is there a better choice of chain for the timing side that is not really heavy?

...is there a better choice of chain for the timing side that is not really heavy?

Any lightweight 8 or 9 speed chain would be a better choice vs. 10 speed, if only for the longer service life of the somewhat larger roller/pin contact faces. I;ve been using the 116 link KMC X9 SL chains in recent years (I stock up when they go on sale); these are pretty darn light at 257g. The 106 link SRAM PC991 hollow-pin and Shimano CN-7701's are also pretty light at 278g - 280g (you have to factor up the weight for the link count to get apples to apples with the KMC) but also fairly durable.

Again, the difference between a light and not as light is usually around 30-40 grams and about $20.

Ok, I'll stick with the Sram chain theme and use the 9spd PC-991 for timing, then keep the 10spd PC-1051 chains for the drive side. I had some Dura Ace CN-7701 chains stocked for our singles, but I wanted to make use of the Power Links with the Sram chains on the tandem. The Sram 991 can be had for a few dollars cheaper too. I wasn't concerned about a few 10s of grams, just didn't want it to venture into the 100s as it would have with a full half-link chain.

I remember when our Santana had first come with a straight link, KMC BMX type chain for the timing side. It was always catching on the sprocket teeth like it wanted to jump off, even when tensioned tighter than normal. It was noisy and clunky looking too. Once we changed to shippable drive type chains with the rounded sides, no more problems and very smooth tracking.

Photos & album updated in the first post :)

Looks Great! So have you and your stoker had it out for it's maiden voyage. What is the current weight without the gates belt?

Wayne

As currently shown, it's 29.5lbs, but some addnl component weight reduction will be implemented. Could lose 1/2lb using the rear rim brake instead of the disc and Ultegra cassette instead of the big XT.

Amazing how it goes from a 7lb frame to something over 29lbs even with lightweight wheels at 1650gms, etc. The stems, seatposts, handlebars all weigh in at the magic number of around 150gm each; saddles at 260 & 270gms; crankset a not so light but stiff 1880gms(?); and so on.

Strategic space left open for GPS, Computer (Polar), etc.

Not ridden with my stoker yet as it's still in the build stage. The slight lack of attention to the crank phasing will be addressed once the Half Links arrive to sort out the timing chain length & eccentric rotation position.

As currently shown, 29.5lbs. Amazing how it goes from a 7lb frame to something over 29lbs even with lightweight wheels at 1650gms, etc.

It is indeed.

The journey to a svelte tandem on a fresh build where you tally all of the grams as they make their way on (and off) of the frame is always an education unto itself in terms of what you discover about the various weight contributions of different components, many of which are sometimes taken for granted. I suspect a fair number of folks who have acquired high-end, lightweight tandems have all taken this journey.

What's more interesting is to look at four different weights as you do a build like this:
- Frame Only
- "Comparison Weight" which is the built-up tandem without pedals, waterbottle cages since this is typically how manufacturers list the weights of their tandems
- Final build weight, which is what most of us probably thing of, where we've now put those pedals and waterbottle cages on.
- As-ridden weight, which is what it actually weights when we hit the road for a ride with pumps, computers, mud-guards, bicycle bells, rear racks, trunk packs with parts or other "stuff", those evil and very heavy filled water bottles, lights and seatpacks* for weigh-in.
*Note: For the folks who eschew seat packs as a cycling fashion faux pas, all the junk they carry in jersey pockets vs. a seat pack needs to be put in a baggie and taped to the frame for a true apples to apples comparison of static bike weight.

Guess which weight is the one that really matters? Yup, it's that last one that represents the total bike mass that you're hauling up those hills or launching in a sprint for the county line sign. I've set up my scales at tandem rallies on Saturday mornings before the ride and offer folks a chance to see just how much their tandems weight as ridden: it's eye-opening to say the least. 33lb tandems can quickly become 46lb - 50lb tandems.

It is indeed.

The journey to a svelte tandem on a fresh build where you tally all of the grams as they make their way on (and off) of the frame is always an education unto itself in terms of what you discover about the various weight contributions of different components, many of which are sometimes taken for granted. I suspect a fair number of folks who have acquired high-end, lightweight tandems have all taken this journey.

What's more interesting is to look at four different weights as you do a build like this:
- Frame Only
- "Comparison Weight" which is the built-up tandem without pedals, waterbottle cages since this is typically how manufacturers list the weights of their tandems
- Final build weight, which is what most of us probably thing of, where we've now put those pedals and waterbottle cages on.
- As-ridden weight, which is what it actually weights when we hit the road for a ride with pumps, computers, mud-guards, bicycle bells, rear racks, trunk packs with parts or other "stuff", those evil and very heavy filled water bottles, lights and seatpacks* for weigh-in.
*Note: For the folks who eschew seat packs as a cycling fashion faux pas, all the junk they carry in jersey pockets vs. a seat pack needs to be put in a baggie and taped to the frame for a true apples to apples comparison of static bike weight.

Guess which weight is the one that really matters? Yup, it's that last one that represents the total bike mass that you're hauling up those hills or launching in a sprint for the county line sign. I've set up my scales at tandem rallies on Saturday mornings before the ride and offer folks a chance to see just how much their tandems weight as ridden: it's eye-opening to say the least. 33lb tandems can quickly become 46lb - 50lb tandems.

You make a very good point but I would add the weight with the team including personal gear is what is really hauled up the hills. Guess you might need a special scale for that.

Guess which weight is the one that really matters? Yup, it's that last one that represents the total bike mass that you're hauling up those hills or launching in a sprint for the county line sign. I've set up my scales at tandem rallies on Saturday mornings before the ride and offer folks a chance to see just how much their tandems weight as ridden: it's eye-opening to say the least. 33lb tandems can quickly become 46lb - 50lb tandems.

This is very true however, the difference between a 40 pound tandem and a 27 pound tandem is still 13 pounds even when you add all of the aforementioned items, it is still 13 pounds less weight to haul up those hills. There is absolutely no way that I would want to go back to our old 40 pound bike.

It will be interesting how much actual weight the belt drive will save over the chain, Ritterview put together a spread sheet and his calculations indicated about 3 ounces, however he was using a very light timing chain in his calculations. When the Gates CDX system is available this winter our Calfee will get upgraded. Primarily to get rid of the dirty chain.

Wayne

This is very true however, the difference between a 40 pound tandem and a 27 pound tandem is still 13 pounds even when you add all of the aforementioned items, it is still 13 pounds less weight to haul up those hills. There is absolutely no way that I would want to go back to our old 40 pound bike.

It will be interesting how much actual weight the belt drive will save over the chain, Ritterview put together a spread sheet and his calculations indicated about 3 ounces, however he was using a very light timing chain in his calculations. When the Gates CDX system is available this winter our Calfee will get upgraded. Primarily to get rid of the dirty chain.

Wayne

It doesn't take a spreadsheet or calculus or physics to determine the weight savings of belt over chain. Drop the two sets of components on a scale and there you go. , basic math. The diff was over a 1/2lb.

Now, I have begun implementing a plan to chop off another 15-20lbs. Meaning, this tandem will be lighter than my wife's single once I'm finished. Component reduction includes: no beer, no salsa & chips, etc. and it has begun to take effect in spite of the sucky weather up here - it's mid April and we're lucky if the temp reaches the high 50s, like last night after work a whopping 57F and trying to rain again. Yikes.

Target weight... -33lbs, 3 decades ago?

Congrats! It looks gorgeous. I think under 30 lbs is amazing for a "real-world" tandem bike that has a rear disc, broad gear range, and comfy stoker hoods.

Thanks. About those stoker hoods (Cane Creek), they are surprisingly heavy +300gms, and after "finger" tightening the clamps the plastic base already started to crack. I wouldn't mind finding some lighter weight, comfy and durable replacements. Wish Calfee made some carbon hoods :)

Thanks. About those stoker hoods (Cane Creek), they are surprisingly heavy +300gms, and after "finger" tightening the clamps the plastic base already started to crack. I wouldn't mind finding some lighter weight, comfy and durable replacements. Wish Calfee made some carbon hoods :)

Yes, I have the Dia Compe ones, and they're heavy also. I'm working with Bob Davis on getting some info on lengths available for CF pegs that are a lot lighter. I've seen the typical short ones in various photos of peoples' bikes, but apparently he might offer a longer version if desired.

I wonder what size is preferable.

Yes, I have the Dia Compe ones, and they're heavy also. I'm working with Bob Davis on getting some info on lengths available for CF pegs that are a lot lighter. I've seen the typical short ones in various photos of peoples' bikes, but apparently he might offer a longer version if desired.

I wonder what size is preferable.

I would like some that are about 30 to 40 mm long. How do I contact Bob Davis?

Thanks, Ryan

I would like some that are about 30 to 40 mm long. How do I contact Bob Davis?

Thanks, Ryan

PM sent to you. Thanks to Rudy for pointing me in the right direction.

Wish list:
- lightweight short or standard reach stoker pegs - small hands.
- carbon stoker stem w/31.8 bar end clamp. ideal seatpost clamp is 27.2, but can shim to any size.

Equipment feedback:

I am liking this new (2012) Avid BB7 version better than the original one we had back in 2003. The new BB7 added the outboard pad adjustment, actuator arm spring adjustment, and better/higher default tension so the arm return has a nicer pull on the brake lever up front.

This new BB7 has a very firm, natural (ie: single bike rim brake) feel, not the soft and mushy slop of the previous version. Although we had good quality brake cable on the previous tandem, I think the Jagwire Super Slick Stainless wire used on this new build is really good no-stretch stuff. I get immediate and solid clamp down on the rear brake (Avid) with zero sponginess.

PM sent to you. Thanks to Rudy for pointing me in the right direction.

Is Bob Davis some sort of stealth businessman? He makes and i understand sells tandems, does he not want his contact info posted?

I have looked at his web site. Tandems look cool but didn't see contact info.

I've successfully used 3/32" half-links on our tandem's sync chains to solve similar set-back issues. It's not a perfect match to 9-speed chains, but since the sync chain is a direct drive it doesn't really matter.

Here is a pic of what you suggested... PC991 (9spd chain) + 3/32" half-link. While the half-link is the same length (1/2") and roller width (3/32") they appear to have no desire to match the height of regular chains. Also, while KMC does have a missing-link parts page (http://www.kmcchain.us/kmclandinga.asp?bsid=34&ssid=682) for each model, they do not provide size or any other specification info. It isn't a perfect link size match but seems to work on the timing side and did let me lengthen the chain by +1 to allow moving the eccentric position to a 5 o'clock orientation.

For my initial install I've used a Sram Powerlink (provided with the Sram chains) to join the half-link to the standard inner PC991 link. The Powerlink is a little on the tight side, so I'll monitor it to see if it works its way in or needs a standard pin/outer link.