Tandem Cycling - In to deep

After 6 months of riding a used speedster that fit "good enough" we took the plunge and ordered a custom Calfee tetera tetra with couplers the other night. Stoker inseam is 6" longer than captains although overall hiegt is only 2" taller so this should be an interesting looking frame can't wait to see what Craig comes up with. We are a 325lb team riding in the San Jose area starting to do some climbs in the Santa Cruz mtns. I do not plan on doing any loaded touring but credit card overnighters are a possiblity. I am leaning toward an Avid 8" disc with a campy dual pivot in front with the option of a dual pivot in back also. Phil wood hubs with 36 or 40? spoke rims of some sort. Does any one run the sapim cxray spokes on tandems? any thoughts on spokes? Campy shifters mated to a shimano mtn rear derailer. Any ideas on a stoker stem with a sharp rise? Does anybody make custom stoker stems? maybe seven or sirotta?

...Stoker inseam is 6" longer than captains although overall hiegt is only 2" taller so this should be an interesting looking frame can't wait to see what Craig comes up with. ...stoker stems?...

For a stoker stem, one solution is to begin with a regular adjustable stoker stem but replace the extendable part with another regular stem turned upward. Below are photos of a Zona custom tandem belonging to a couple we met at the recent Tennessee Tandem Rally with a stoker who was much taller than the captain. Their stem is a custom stem from Zona but you can do the same thing with off the shelf parts.

Bloomington, IN

...Calfee tetera tetra with couplers the other night.

Congrats, but just to make sure you get off on the right foot the nomenclature for your tandem would be a Calfee Custom Tetra Tandem... only a few Calfee Tetra Tetra tandems were built very early on.


I am leaning toward an Avid 8" disc with a campy dual pivot in front with the option of a dual pivot in back also. Phil wood hubs with 36 or 40? spoke rims of some sort. Does any one run the sapim cxray spokes on tandems? any thoughts on spokes?

Brakes sound about right, but you might want to rethink your hubs: 634 grams for set using the rear thread-on disc version and 735 grams for the bolt-on rear disc hub. You might want to consider a set of White Industries (380g / 424g) or Chris King hubs (### / 532g). We've had great success with the White Ind. hubs which are very light (I use the MI5 MTB front hubs vs. the tandem front hub) and a great value with outstanding customer supportas well as the Chris King hubs which whilte a bit heavier and more expensive have taken the top stop for durability and engineering. Phil Woods hubs have also served us well, but in addition to being old-school heavy, quality has been a bit spotty. Thankfully, their customer support and warranty coverage is second to none. CX-Ray spokes require a very good wheel builder and are about twice the cost of the other Sapim spokes for a margin improvement in performance.


Does anybody make custom stoker stems?

If cost is no object, Calfee offers the BarStems ($$$$) which I'm sure he'd be happy to sell to you and any of the better custom builders can make a custom one-piece stem ($$). You might also check with Mark Johnson at Precision Tandems to see if his carbon stem supplier -- Bob Davis / Zona tandems -- would be willing to make something for you ($$$$). Bloomingcyclist's suggestion is also a good one and most of the better tandem speciality dealers (http://www.tandemseast.com/parts/stems.html) have a large collection of stoker boom components that can be assembled into a variety of configurations.

Thanks for the input, the stoker stem issue has had me scrathing my head. Did not realise there was such a dramatic weight penalty on the PW hubs. Can CK's be had with 40 hole spkoke pattern?

"CX-Ray spokes require a very good wheel builder and are about twice the cost of the other Sapim spokes for a margin improvement in performance."

Just curious as do what the issue is that requires special attention by the wheel builder, I do have a set wheels for the single that has these spokes and so far so good.

Can CK's be had with 40 hole spkoke pattern?

No, but the White Ind. can. However, 36 is probably OK so long as you and your stoker don't plan to put on another collective 30 lbs or so.


Just curious as do what the issue is that requires special attention by the wheel builder

Knows how to keep bladed spokes from widing-up during the build and getting the tension right...

I have the same WI combo as Tandem Geek. Except I have 36h front and 40h back.

BTW Chichi, this is Marco. I met you around Coastaoa on the Sequoia Century, right??

with a team weight of 325 lbs why are you considering 40 spoke wheels?

If you're shelling out for an expensive, light CF tandem, I'd want some lighter wheels; ROlf, topilino, or zome Zipp 808 rims laced to 145 mm hubs,or something along those lines.

If you're shelling out for an expensive, light CF tandem, I'd want some lighter wheels; ROlf, topilino, or zome Zipp 808 rims laced to 145 mm hubs,or something along those lines.

If I could only have one set of wheels for our 'C' bike they would be the ~2,000 gram conventionally spoked wheels with a deep section rim: they do everything very well and are easy to live with. You're talking $550 - $650 for a nice set of wheels like this.

Once you have those, knock youself out and pick-up that second set of wheels. A summary of the four different sets of wheels we've used on our tandem can be found here (http://www.thetandemlink.com/calfee_tandem_build.html).

We finally rode on our newest wheels today... coincidentally the White Ind / Velocity Deep-Vs... and they felt wonderful. I fitted them with 25mm Vredestein Fortezzas instead of the 23mm VFs we've used for the past 1,500 miles on the other three wheelsets just to estalish a new baseline for future comparisons. Rock solid, precise handling, comfortable, and no worries about dinging a rim on a pot hole: a spare black Deep-V is hanging in the shop along with two ti-grey ones on hand for our Erickson's wheelset.

We'll likely run these for a few weekends on the 'C' bike and then put them on the Erickson to do a frame comparison sanity check. After that, they'll go back on the 'C' bike for a Saturday ride and then we'll fit the Rolf's with 23mm tires for a Sunday ride to see if we can detect any significant performance difference via perception or in comparing data from the Garmin & HAC4. We'll do the same with the Topolino's in August just for the heck of it, noting that the Topolino's are not marketed as 'aero' wheels, simply a very lightweight but very robust and comfortable wheelset.

Zipp 808 rims laced to 145 mm hubs,

Maybe if it was a TT bike.

Those are pretty damn deep section, and not very light (727g for clincher)

With nice rims/hubs/spokes conventional wheelsets are often lighter than boutique sets.

I am leaning toward an Avid 8" disc with a campy dual pivot in front with the option of a dual pivot in back also.

Campy Record rear brake is a single pivot. We put a Zero Gravity Negative G in the back and it feels a little beefier. Will mount same on front as soon as I sort out fork clearance issue (ZGs do not clear fork blades of Alpha Q X2).

"Campy Record rear brake is a single pivot"

Why not take a front brake and put a rear bolt in it?

Marco, yes I did meet you and Ruth on the Sequoia.

My thinking on wheels is to start with something that is of reasonable weight, very relaiable and servicable, and then add a set of lightweight wheels for local moderatley hilly rides.
I am interested in seeing how the topolinos hold up on tandems, I had the original hub design on my single loved the ride but had the rear hub on drive side crack 3 times. Topolino seems to have fixed the problem and no problems for last 6 months (2500 miles)

BTW how do you quote messages in reply?

Campy Record rear brake is a single pivot.

True for most post '02 Campy Record and Chorus... however, if you don't mind using NOS or used Campy brakes you can usually find the older models where both the front & rear calipers use the dual pivot / differential configuration.

Our '98 Erickson has a set of pre '02 Campy Record dual pivots and I have a second set sitting on the shelf that came off of the 'C' bike when I gave into vanity and installed the '08 Record Skeleton brakes which only use the single pivot for a rear brake. I think I have a couple sets of Campy Chorus dual pivots on my single bikes.

The single pivot rear brakes do a great job of approximating rim brake noise and generating heat when insatalled on a tandems rear wheel, but not a lot of actual stopping power: kinda like a Harley Davidson which is very efficient at converting gasoline into noise and CO2 without the pesky side-effect of horsepower.

Anyway, I guess my point is if you shop around you can find the older Campy Record / Chorus calipers with the rear dual pivot / differential brakes. I also suspect that you could convert a front differential into a rear by swapping out the mounting bolt and changing the orientation of the brake blocks by swapping left for right. At our combined weight of 285 lbs, the single pivots have been "good enough" for all but the most demanding terrain. Like our previous travel tandem, if we venture into any real mountains I'll install our Avid BB7 in place of the rear caliper and use one of our wheelsets that's disc brake compatible.

"Campy Record rear brake is a single pivot"

Why not take a front brake and put a rear bolt in it?

Marco, yes I did meet you and Ruth on the Sequoia.

My thinking on wheels is to start with something that is of reasonable weight, very relaiable and servicable, and then add a set of lightweight wheels for local moderatley hilly rides.
I am interested in seeing how the topolinos hold up on tandems, I had the original hub design on my single loved the ride but had the rear hub on drive side crack 3 times. Topolino seems to have fixed the problem and no problems for last 6 months (2500 miles)

BTW how do you quote messages in reply?

BTW how do you quote messages in reply?


Look in the lower right hand corner of the message that you are interested in quoting and you'll see this:

[reply with quote]

Click on it and it will automatically quote the entire post. However, I always recommend only the actual part of the post that you'd like to respond to be included in the quote and that all other extraneous comments be deleted.

[reply with quote]

I always recommend only the actual part of the post that you'd like to respond to be included in the quote and that all other extraneous comments be deleted.[/QUOTE]


Think I got it.

Thanks

Maybe if it was a TT bike.

Those are pretty damn deep section, and not very light (727g for clincher)

With nice rims/hubs/spokes conventional wheelsets are often lighter than boutique sets.

2000g for the set built on White Industry hubs. Msybe not the lightest, but they would be smokin fast.

Think I got it.

Almost, but not quite...

You need to make sure you don't delete the first HTML command line:

[QUOTE=TandemGeek;6889949]

It's what tells the software you're starting a quote and who you're quoting....

The Mavic SSC are the best dual pivots for stopping power (IMHO). I have tried several brakes (Campy, shimano, tektro, etc..).

I have the SSC on my single, and they are CRAZY. You know that feeling when in a car with a really good ABS, vented disc, etc brake system, with nice sticky tires, and the brakes absolutely haul the car down at speed (on the verge of getting seatbelt marks on your chest, etc.. ;) ) I get that same type of feeling on my single bike.

I am sure they would work well on the tandem (for a light team). I would use them if my fork/frame were drilled for calipers.

For a stoker stem, one solution is to begin with a regular adjustable stoker stem but replace the extendable part with another regular stem turned upward. Below are photos of a Zona custom tandem belonging to a couple we met at the recent Tennessee Tandem Rally with a stoker who was much taller than the captain. Their stem is a custom stem from Zona but you can do the same thing with off the shelf parts.

Bloomington, IN


Anyone know where I can get a "regular" stem like that? Is it a quill?

Anyone know where I can get a "regular" stem like that? Is it a quill?

Check with Tandems East (http://www.tandemseast.com/parts/stems.html)or Precision Tandems (http://www.precisiontandems.com). They both have a plethora of stem configurations

The Mavic SSC are the best dual pivots for stopping power (IMHO). I have tried several brakes (Campy, shimano, tektro, etc..).

I have the SSC on my single, and they are CRAZY. You know that feeling when in a car with a really good ABS, vented disc, etc brake system, with nice sticky tires, and the brakes absolutely haul the car down at speed (on the verge of getting seatbelt marks on your chest, etc.. ;) ) I get that same type of feeling on my single bike.

I am sure they would work well on the tandem (for a light team). I would use them if my fork/frame were drilled for calipers.


Absolutely correct, great observation on the SSCs. They'll be gracing our newest build on front and rear. I've also used them on singles and they bring the speed down fast and controlled with an excellent feel. Another factor I like is you don't see them on many bikes which adds to the "cool" factor.
I'd rate them as the best dual purpose I've ever used. They're certainly not the lightest but they're made incredibly well, look slick, don't cost an arm and a leg and work with power to spare.

KRhea

The Mavic SSC are the best dual pivots for stopping power (IMHO).

I'll opt out of the stopping qualities debate and only add that Mavic's calipers are best suited for the folks who use Campy Ergo shifters.

Mavic's brake calipers, just like Campy's own brake calipers, do not have a brake release mechanism often times needed to allow removal of wheels fitted with 25mm or 28mm tires. Instead, Campy and Mavic's brake rely on the brake release mechanism that resides in the Ergo lever.

The Mavic SSC are the best dual pivots for stopping power (IMHO).

I'll opt out of the stopping qualities debate and only add that Mavic's calipers are best suited for the folks who use Campy Ergo shifters.

Mavic's brake calipers, just like Campy's own brake calipers (Chorus-D skeleton pictured), do not have a brake release mechanism often times needed to allow removal of wheels fitted with 25mm or 28mm tires.



Instead, Campy and Mavic's brake rely on the brake release mechanism that resides in the Ergo lever.

Shimano's shifters do not have a brake release and, instead, rely on the cam lever mounted where the brake cable attaches to each caliper.

I'll opt out of the stopping qualities debate and only add that Mavic's calipers are best suited for the folks who use Campy Ergo shifters.

Mavic's brake calipers, just like Campy's own brake calipers, do not have a brake release mechanism often times needed to allow removal of wheels fitted with 25mm or 28mm tires. Instead, Campy and Mavic's brake rely on the brake release mechanism that resides in the Ergo lever.

Excellent point. I meant to mention that as well and forgot, way to cover the "fine points" Geek. Without having that Campy lever release it would/does/can make wheel removal a pain in the butt.

KRhea

I have and old set of Campy dual pivots that I may use unless the black Mavics just look better. I am also thinking of running an Avid BB7 with a friction bar end and something like an IRD interceptor* on the drop portion of the bar. You could alternate between the rim and disc brake to minimise heat build up on either surface or run the disc as a drag brake in severe situations. Somebody also told me they ran calipers with a splitter off of the left brake and the disc off of the right. Worked well but did require attention to keep both calipers in sync.

*IRD only offers in silver will have to start looking for something in black.

I wouldn't complicate things. Have the frame setup to mount a disc. Then just run dual pivots, until you find a need for a non-rim brake.

Without loaded touring, the dual pivots will serve you fine (used properly).

I agree with the positive comments on dual pivots. We are now comfortably into the first 600miles
on our new bike. As mentioned,..we went with ZG,..and after I figured out that the closing the brake release was critical to stopping power, all was good. I feel pretty confident going down shortish ( less then a mile) medium grades (8%). Of course my stoker is still asks for speed control,...so we never let it get too out of hand.

I also have SSCs on my single,..and have used them for 4 yr or so,...mostly for the bling. As mentioned, it's a pain even getting 23s on and off with my shimano levers.

Good Luck!! You have a great project going.

just run dual pivots, until you find a need for a non-rim brake.

.

My concern is that when I find out that dual pivots are not enough, I won't have time time to mount a non rim brake before the point is realy driven home:D .
All kidding aside I think it woud be better to start with overkill and then remove equipment if I am not using it. San Jose area has lots of hills in the 3 to 7 miles at 5+% grades(8-10% is not hard to find either). My wife is having a lot of fun after not being on a bike for about 30 years I don't want to scare her away because I was trying to save weight, money or was not paying attention to details.

I wouldn't complicate things. Have the frame setup to mount a disc. Then just run dual pivots, until you find a need for a non-rim brake.

Without loaded touring, the dual pivots will serve you fine (used properly).

If you do long, steep and twisted descents and your team weight is at or above 300 lbs, a non rim brake comes very handy and makes for a more enyoable ride. Anything longer than a mile with sharp turns and >7% grade has your mind thinking about tires/heat ....

My concern is that when I find out that dual pivots are not enough, I won't have time time to mount a non rim brake before the point is realy driven home:D .
All kidding aside I think it woud be better to start with overkill and then remove equipment if I am not using it. San Jose area has lots of hills in the 3 to 7 miles at 5+% grades(8-10% is not hard to find either). My wife is having a lot of fun after not being on a bike for about 30 years I don't want to scare her away because I was trying to save weight, money or was not paying attention to details.

Understood. However, a complicated system is not a good solution and discs aren't a good choice for a drag brake.

I would either go with (1) DP front and back, (2) Disc front and back, or (3) DP front, disc in back. Options 2 or 3 would be the way to go if you want a non-rim brake.

Also FWIW, I live in the same area. Every ride I do is hilly. I descended Mt. Hamilton with no stops, and the long descents from Sequoia (like HWY 9), Kings Mtn, East 84, West 84, Alpine, etc, etc... I did all of those with just Cantis.

Our team weighs 295 lb but our bike is around 40 lb, so it's probably a wash.

Taking the right lines, not letting the brakes drag, alternating brakes, later braking all help you go faster, and demand less heat capacity from the rims/brakes.

All I am saying is I would not install a caliper and a disc on the same wheel. Most certainly not with any type of proportioning control activating both at the same time.

A complicated system is not a good solution and discs aren't a good choice for a drag brake.

I would not install a caliper and a disc on the same wheel. Most certainly not with any type of proportioning control activating both at the same time.


I have gathered that discs are not a good drag brake, that's why I thought the idea of being able to use them alternatley with the dual pivot would be a good set up. Running both brakes off of a single lever does not apeal to me and both back brakes sounds particularly bad. However the person that told me they were running buth dual pivots off of 1 lever and the disc off the other seems to know what he's doing. Regardless of what I do you can bet that the first run will not be down Mt Hamilton, Hwy 9 etc. BTW how is hicks heading toward new alamaden, it's right in my backyard and I have been thinking of giving it a go.

BTW how is hicks heading toward new alamaden, it's right in my backyard and I have been thinking of giving it a go.

Haven't done it. Maybe worth a try?

HWY 9 was an awesome descent. We were hitting 45+ between turns.

I am in San Mateo, so the mid-peninsula is more local to me. My favorite descent around here is Kings Mtn.

We hit 50.6 on training ride last week and we were not pedaling. Bike felt very stable. Rode is wide open, excellent surface and closed to through traffic. If they would just remove those traffic barriers at the bottom.

am also thinking of running an Avid BB7 with a friction bar end and something like an IRD interceptor* on the drop portion of the bar. You could alternate between the rim and disc brake to minimise heat build up on either surface or run the disc as a drag brake in severe situations.

Glenn Erickson had the same thought a few years back, i.e., keeping the rear rim brake on a disc equipped tandem as a 'belt and suspenders' configuration for anyone who was concerned about relying on one or two disc brakes or giving up a true drag brake (Arai) when heading into seriously challenging descents. By seriously challenging, these would be the long descents down the switch backs of epic European mountains where 'letting the run' just isn't an option for a safe and controlled descent.

His proposed configuration put the rear rim caliper under the control of the stoker using a bar-end shifter or small cross-bike / in-line type brake lever with the rear disc being used as the primary rear brake controlled by the captain. The front brake was controlled per normal. The purpose of the supplemental rim brake was two fold:

- On very long descents, often times it's hand fatigue that can get the better of the captain and by giving the stoker control of a supplemental brake, the captain would be able to give their right hand a break while the stoker momentarily assumed rear brake control to keep the speed of the tandem in check.

- Also on very long descents, should continuous braking begin to cause a rear disc to out-gas and fade, the stoker could take over rear brake control working in tandem with the captain's control over the front brake and/or just to give the rear brake some extra time to cool as the tandem continued the descent.

In regard to the latter, ironically once a brake device and tire/tube/wheel have gotten to a point where they are overheating, stopping can become the coup de grace for one or more of those components, noting that it will take a maximum braking effort to actually make the stop (generating massive heat) while, at the same time, the brake-cooling effect of descending is reduced and then completely removed exacerbating the potential for heat-related damage to the brake device and tire/wheel/tube.

Anyway, I bring this up only to note that at least one of the most well-respected tandem builders has considered this option and to elaborate on the theory and related issues.

My recommendation? When in serious doubt, install an Arai drag brake. Worried about weight, install a shaved Arai drag brake. If you're simply looking for additional heat capacity "just in case", the Avid BB7 with 203mm rotor has proven to be a great solution for light to mid-weight teams who must cope with demanding descents on an occasional basis. In any event, so long as you plan ahead when building and spec'ing the components on your tandem, i.e., I.S. disc brake mounts & disc compatible rear hub with perhaps the necessary cable stops added, you can always reconfigure your tandem for different conditions or trips. Our current tandem will most likely run nothing but Campy Skeleton brakes front & rear for 95% of it's life. However, it can be switched over to an Avid BB7 in about 30 minutes with parts that are already on hand. Of course, the trick here is you need to be sure to break-in the disc well before you actually need it, otherwise you can almost be guaranteed to have problems if the first duty it sees is on a very long and demanding descent.

Went out tonight and did a test ride with current equipment on a local hill (Hicks) 1.66 miles at 8.6% 1 mile section at top is 11.1%. Told my wife goal was to see if we could make it up the hill, didn't tell her the real goal was to see if we could make it down. Current equipment is Avid bb7 in back with shimano organic pads and Avid Vbrake with some type of Avid stiffiner in front. Things worked reasonably well, with exception of some sqeal when only 1 brake at a time was applied. I stopped half way down to check rims for heat and that seemed to be okay. I think I will take TG's suggestion and set the bike up to run both disc and dual pivot in back and then do some experimenting. 50.3mph on the other road again no pedaling!

PS is there a spell check on the message board?

We have Campy Record dual pivots front and rear and have had no issues. With 25 tires they are a bit tight coming out so 28's and larger would be more difficult. We are about 350lbs and stop much better than what we originally had [DiaComp canti's]. It was worth the extra money spent for the brakes, replacing the brake bridge so it could take the caliper at the rear, and painting the frame.