my Calfee Tetra build
#1
Clipless in Coeur d'Alene
Thread Starter
2012 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).
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.
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/1095507...eat=directlink
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.
Code:
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)
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/1095507...eat=directlink
Last edited by twocicle; 05-13-13 at 12:09 PM.
#2
Senior Member
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.
Very nice color.
#3
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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.
#4
Clipless in Coeur d'Alene
Thread Starter
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?
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?
Last edited by twocicle; 04-09-12 at 05:26 PM.
#5
Senior Member
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.
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.
#6
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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.
#7
Clipless in Coeur d'Alene
Thread Starter
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.
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.
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.
Last edited by twocicle; 04-09-12 at 06:58 PM.
#8
Clipless in Coeur d'Alene
Thread Starter
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.
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.
Last edited by twocicle; 04-16-12 at 09:17 PM.
#9
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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.
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.
#10
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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.
#11
Clipless in Coeur d'Alene
Thread Starter
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.
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.
Last edited by twocicle; 04-13-12 at 03:08 PM.
#12
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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 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.....
#13
Clipless in Coeur d'Alene
Thread Starter
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 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.....
Last edited by twocicle; 04-13-12 at 08:25 PM.
#14
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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 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.
#15
Clipless in Coeur d'Alene
Thread Starter
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.
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.
#16
Senior Member
Sounds good, what are you waiting on in order to finish the build?
#17
Clipless in Coeur d'Alene
Thread Starter
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.
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.
Last edited by twocicle; 04-14-12 at 01:43 PM.
#18
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What's the seatpost diameter?
PK
PK
#19
Clipless in Coeur d'Alene
Thread Starter
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.
Last edited by twocicle; 04-16-12 at 03:53 PM.
#20
Clipless in Coeur d'Alene
Thread Starter
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
Maybe the guys at the bike shop are playing a joke on us and dumped some lead weight in the seat tubes
Last edited by twocicle; 10-17-12 at 11:51 PM.
#21
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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.
#22
Clipless in Coeur d'Alene
Thread Starter
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: https://www.precisiontandems.com/cat_...r&geometry.htm
Mark Johnson has the geometry posted here: https://www.precisiontandems.com/cat_...r&geometry.htm
Last edited by twocicle; 10-17-12 at 11:49 PM.
#23
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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:'
https://www.co-motion.com/index.php/i...ng_belt_system
#24
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So, are you using the 11-28 or 11-34 cassette?
Currently my tandem is experiencing the chain length, rear derailleur capacity issue.
Currently my tandem is experiencing the chain length, rear derailleur capacity issue.
#25
Clipless in Coeur d'Alene
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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).
Last edited by twocicle; 04-17-12 at 09:19 AM.