PoeCo

I think the suggestion comes from wanting to get the best fit/handling combination for our smaller height. We definitely don't ride flat terrain (we're in Colorado and ride lots of hills and even into the mountains at times), and we don't need an ultralight tandem. The builder isn't saying that we "can't" build with larger size wheels or have disc brakes, but I can feel the urging toward 26" wheels and rim brakes.

geoffs

I just wouldn't even contemplate getting a rim brake tandem these days unless you were trying to build one that was ultra light and every gram counts.
As to the weight difference between disc and rim brakes if you are riding lots of hills, with rim brakes you would need to use a drum brake as well. The additional weight of a drum brake when you add it to the rim brakes will most probably be more than just disc.
Using disc brakes means it's an easy swap between 650b and 26" wheels.
I would be suggesting that you find another builder. We have a custom Co-motion Mocha with S&S couplers and 26" wheels (ours will be 13yrs old in a few months so bought before 650b was a thing) that we've been very happy with. We required a custom frame do to a 11" height disparity between myself and my lovely stoker

Mike Ayling

(The speedhub was set for me) What exactly do you mean by this?

I know that Rohloff requires a minimum chainring/sprocket ratio (used to be 2:1) to maintain the warranty.
Gtreater than 2:1 good, less than 2:1 bad and I have heard that German mechanics refuse to equip a bike that will infringe the ratio.

You certainly can purchase the hub seperately outside Germany.

We have a Thorn touring tandem with 26 inch wheels which work well for us.

BTW we have the 32 spoke Rohloff hub.

Mike

PoeCo

We have visited the Tandem Cycle Works shop in Denver a few times over the last several months and decided against them as they don't seem to understand our needs. I'll leave it at that as I don't wish to disparage a shop that I know has done good things for others. The shop owners were always very nice, but it just wasn't the right fit for us.

We have a limited budget for this tandem since we just bought the other one toward the end of last year that doesn't fit. So, we went to a shop that have built tandems for several decades and that I have a prior experience using to build a custom single bike. I am of the 'trust but verify' mentality, especially with something as expensive as a custom tandem build.

We and the potential builder have had conversations since the first post which has helped to clarify what we were thinking as well as what the builder believes to be a good choice for us, so we are feeling more confident that we are heading in a good direction and that we are being heard.

Our initial question regarding wheel size was an attempt to make sure that we weren't just accepting one persons opinion or thoughts regarding the build without knowing what others use or what works well for other teams. It's difficult to compare because our team is short (5'3.8" captain and 5'1" stoker - both of us have short legs even respective of our heights - ugh) and many tandem teams have a taller captain, but we just didn't want to make a decision and then regret it later.

At minimum, we felt more comfortable hearing from others so that we could try to understand better what any potential downfall could be with larger or smaller wheels/tires specifically on a tandem. We both ride singles with 26", 650b, and 700c wheels, so we weren't sure what sort of differences we should expect to encounter on a tandem with the same size wheels, if any. We understand that toe overlap is a much bigger deal on a tandem with shorter riders, but we also didn't want to exclude a certain size if it would provide some type of benefit.

The biggest issue we have is that nothing fits us even remotely close enough to truly test (which would always be my first suggestion to anyone looking at such a huge purchase), so it's a more challenging process to decide which path to take.

Thank you for taking the time to respond and offer your thoughts. It's definitely of benefit to hear from others - and particularly those who have a lot of experience and mileage on tandems. We greatly appreciate it!

PoeCo

We actually looked at the Mocha (obviously the new version with 650b wheels though) as it seemed like a potential option for a tandem that could travel well on paved and dirt roads. Good to hear that someone has enjoyed their Mocha for so many years! I actually went on a hunt trying to find reviews from other tandem riders on this model and it wasn't a very productive search, so it's good to hear from someone who has enjoyed theirs for so long. Quite impressive.

waynesulak

My opinion is that grouping all tandems by wheel size is a mistake. There are good and bad bikes using all sizes. Same with frame material.

The first decision to make on a custom bike is what tire type fits your riding. That could impact the wheel size selection and will dictate the type of frame and components you chose. Bad tire selection can make any bike faster/slower, comfortable/uncomfortable, reliable/unreliable depending on how they are used.

All but the worst bikes will not slow you down. Bikes are not fast - riders are. We have owned different types of tandems and are most happy with our final choices. While we enjoy them much more than our previous bikes they are only very marginally faster.

Over the past 10 years and four tandems of tandem riding I feel are bikes have improved a lot but we have aged and gotten slower - go figure.

scycheng

By the way, do NOT use a disk brake as a drag brake. There isn't enough mass to absorb the heat. The disk rotor will overheat and do things like warp or melt.

DubT

The wheel selection in my opinion is a really big deal. Wheels have been an issue for us for years. How many spokes, what rims etc. On our current bike we are on our 4th set of wheels. The original build utilized Bontrager tandem wheels, no real issues but they are very heavy. I still have them hanging on the wall. Second set were Topolino, light comfortable but had rim issues, still have them stored away and then I went with Spynergy wheels, good wheels no issues but I have always liked the Hed 3 wheels and modified the rear of the tandem to accept the Hed 3. We now have probably 25,000 miles on the Hed wheels and those are the wheels we sill run. I have them on my single so I have a backup set if needed.

So 26", 650 or 700? Whose wheels will you use and what tires? Are they readily available if you are traveling and need a spare? All questions that need to be considered? Who makes or builds tandem specific 650 wheels?

As for front wheel toe overlap, we have it and it is something you learn to live with.

What about tubeless tires?

What about building it as an ebike? We added a Bafang BBSHD motor to ours and absolutely love it!

Just additional thoughts for a new build.

lichtgrau

Funny this. They (Rohloff) even have price lists with retail prices. You just can't buy the "Coca Cola Can" separately. Not here in Germany. Unless you know a dealer who's willing to take the "risk". I mean... finally I got their idea: They really want to keep their reputation of a more or less undestroyable (or at least very reliable ;-) hub gears. And they want to be as sure as possible to have someone building a wheel knowing what he's doing
The first challenge for me was to pick the right hub out of a growing variety. Rohloff is trying hard to fit their product into most dropouts. Wasn't sure to find a matching hub for our frame in the beginning but that worked really perfectly with their own measuring and adaptation system. I like...

lichtgrau

Sorry (I'm not in my native tongue), by "was set" I meant that I was really determined to equip our tandem with the Rohloff: It has the "tandem-admission", an ideal and constant chain-line, a good range of gears and a perfect forgiveness if I forget to change gears before we stop.
And (most important of all) I had the budget allowance from the stoker

Yes, there is a limit in the chainring sprocket ratio. But that's really hard to determine and (if at all) on a tandem (because of the bigger forces) surely more important than on a single bike. Our current setup is 42/16 with 26" wheels. Works perfectly so far.

We have the 36 spoke Rohloff.

Monoborracho

It is interesting that one of the major tandem builders (located in Cal, used to run small tours and now runs 100+ tours on boats, builds off size head tubes, and everything in his wheelhouse is the best, but has great web site) used to strongly advocate 26" wheels and no lateral tubes, but now doesn't even feature 26" wheels as a good choice.
26" wheels are a great choice for a tandem. And most of us aren't racers.


There....said my piece. And yes, we had a 26" wheeled tandem for our first. Now have two sets of 700 wheels for my current tandem.

kevrider

do you have a 700c road bike single? what is the ETT and do you have toe overlap problems?

you pay a custom builder to get the bike that you want, not the bike that the builder thinks that you should have. we plan to get a Performer Duet road tandem which has 700c wheels and an ETT of 530mm, iirc, roughly the same length as my wifes road single. she should be able to captain our tandem, if she felt the need, she is 5'3" and the fit will be fine for her.

PoeCo

Hmm... that is interesting. Thank you for your experience/thoughts. We've appreciated reading what so many have had to say regarding wheel size. And, as you said, we aren't racers, but we don't want to hinder ourselves either.

PoeCo

I do have a 700c single with a 52.2cm eff top tube. I don't have any problems with toe overlap on the bike. It's close, but no problems.

While we do appreciate feedback and suggestions on what would be most valuable in a tandem from the builder, I do think it's important that they build what we've asked for. It's too much money to not get what we expect out of the bike!

Dean V

If the captain is tall enough to ride a 700c bike without having to compromise frame geometry that is what I would go with.
Disc brakes front and rear and able to take at least a 700c x 32mm and a 650b x 2.1" wheel/tyre combos.
No rim brakes.

scycheng

A lot really depends on what your intended use for the tandem will be. If you will stick to pavement riding, 700C is fine if a frame can be made to fit the captain that doesn't compromise too many things. We had 700C tandem for many years before switching to 26" wheels for credit card touring. The reasons we switched are:

• 700C wheels are a tight fit into standard S and S hard cases
• We wanted bigger tires for touring on non-paved roads/paths. Note for 29er advocates, see point #1. Note for 650b advocates, see next point.
• Parts availability in small towns and villages. Tandem specific parts are hard to find anywhere away from home. The last thing I want is hard to find "ordinary" parts.

As for brakes, either calipre or disc brakes are fine. Each have strength and weaknesses. The key is knowing how to use your tools.

However, do not use disc brakes as a drag brake. It's a bad idea. There just isn't enough thermal mass in the rotors. If you need a drag brake, buy an old Arai brake or a more modern replacement drum brake (Tandem East?). The builder who suggested a disk brake as a drag brake is an idiot.

akexpress 

My wife who is 5'6" routinely captains our tandems. We ride small /small frames. We have 5 tandems that have 700C , 700c/650B, 29r, 26, and fattire tandem with 5.0 tires. The first three have couplers and we travel very frequently in S&S cases. I take the tires off all of the wheels except the 650b to fit easily into the cases. Zero question in my mind that the 700c wheels with 28mm tires are faster by far. The bike that takes 700/650 is faster on the same course with same riders on the 700c by as much as 20%. The 700c with 35-37 is a close compromise with not a huge difference in speed, again same bike ,same riders, on same course . We worked hard with the frame maker to allow a good riding bike with an ability to ride two different wheel sets for different conditions. We can fit up to 47mm tires on the 650b wheels . We do have some toe overlap but it has never been an issue in many thousands of miles of riding. There are a huge number of tire choices for 700C and now many options for 650b. We ride disc brakes on all the bikes now so no adjustment between the wheel sizes. I think an another important issue to decide on a custom frame is the axle system you pick. We use thru axles on all of the tandems. The two road/adventure tandems use 142/12 on the rear and 100/15 on the forks. This is now a very common mtn bike standard and in a pinch if we had a wheel failure we could go into any bike shop and buy a 29r wheel or 650 wheel as a replacement. There are lots of choices to make on a custom frame
but it is a fun process. Enjoy

lichtgrau

Reading all those interesting thoughts and reflecting what is finally most important to me when it comes to wheels on our tandem - stability seems to be my first preference.

If we would talk about single bikes this would really be one of my smallest concerns: My 165 pounds (including gear ;-) plus bike had never bought any of my 28" wheels to its limits.

But tandems are a different species. In addition to my weight, we have the bike (45 pounds), the stoker (0 pounds, who would say something differently ;-) , some miracle additional weight (140 pounds) plus finally some tour luggage (90 pounds). Sums up to 440 pounds. We're still talking about components originally made for standard bikes, no specially reinforced equipment.

So frame, wheels and brakes are most important to me here. With the frame I have to trust the designer/welder. What I do. The four piston disc brake is something I've trusted from the first moment I've tried it. So the wheels are left. When I went around for some builders for our tandem wheels everyone of the three I asked talked about the higher stability of the 26" wheels. I found some sources that say 30% (using the same material) but I never found any detailed calculation on that. However, those experienced guys stated, that it won't be likely that I'm going to meet any material problems with this 26" stuff and they didn't give me the same guarantee for 28/29". Again, we were talking about fully loaded tandems. Those 30% increased stability (even if it's only 25% or less) are still in my mind when we're going downhill with that thing and when I leave the Magura levers untouched...

peterraymond

All the major tandem companies also make custom sized frames and have a wealth of experience. I think that matching the geometry of a single bike gives different handling on a tandem, so no one can extrapolate what they know about singles over directly. Talk to some tandem riders about the differences in how those major brands handle and then pick your company.

I think this gives you the best bet for getting the bike you want, and at the best price.

I saw a rolling resistance test comparison between a bunch of tires and what I saw was that the differences due to size were swamped by the differences between models. I suspect the same is true for rim diameter. The overall diameter difference is not huge and rolling resistance is not directly related to diameter.

But for wheel size you can really just go with your personal prejudices. I think you can see that whatever you chose there will people here who agree 100% and people who think you are dead wrong.

peterraymond

You might Google comotion what-wheels-are-best-for-tandems. It relates a fair amount to the speed where you spin out, but is still interesting.

Monoborracho

One more point which new riders might wish to consider...... in my experience the 26" wheeled tandem was (and is) much easier (and forgiving) to handle at slower speeds, quick or sharp corners, and those oh-so-fun moments when stoker and captain get a bit out of sync, etc.


I came into tandem riding at age 55 with years of road bike riding and my stoker with a couple of years on a cruiser/hyrbrid. Just a thought.