Our tandem team comes in at 400#. We have an opportunity to buy a nice used 2003 Burley Tosa road tandem, but with so much discussion going on in other parts of the internet about wheel sizes, I'm starting to wonder if buying a 700c wheeled tandem is a good idea for us at all?

Yes, we are still considering a 26" bike, but the price on this Burley is hard to beat. If we get this bike, it will be for road use only...no dirt riding. I just want to make sure we won't be "busting rims" every time we go for a ride!

And yes, the roads can get kind of rough around here...being in the U.P. of Michigan and all...

Thank you again.
Andy and Vickie

What wheels come with the bike? I doubt you will have any issues with 40-hole wheels and I know you will be OK with 48's.

You can ride groomed trails and gravel roads with 700c wheels. We do it all the time and our team weight is.... is... is... I will say 360lbs, but it could be 370....

We have a 2005 Tosa spec'd with White Industries hubs and the Weinmann DPX 40-hole rims, and our team was 360, down to 350 (ah, dieting--the best way to shave pounds off the bike). We've had to true the rear wheel once already when it developed a wobble at about 300 miles of use. Since then it's been no problems. Overall the wheels have been quite sturdy, and we get great performance with a pair of 700x28 Continental Grand Prix 4-Seasons. I swear they roll faster than the stock Panaracer Paselas that came on the bike.

I think the Tosa is a great frame for a heavier team--we've been very happy with the responsiveness and stiffness of the frame, and the frame hasn't changed from 03 to 05 as far as I know. It can start to feel a little TOO stiff on longer rides, though, so I have a Wound Up carbon seatpost and Mollie has the Rock Shox post in the stoker's seat. Now things are nice and plush.

Good Luck!
DrPete

I'll echo DrPete's comments. We also have a 2005 Tosa with the same wheels and the stock tires. We're almost 400 pounds and haven't had any issues with the wheels. We did have a pinch flat once, but otherwise no issues.

Yo Yoopers!

Should not present a problem; avoid the deep chuckholes and the snowdrifts!
Run 28mm tires or larger and it'll work out just fine.
Good luck and welcome to the club!

Pedal on TWOgether!
Rudy and Kay/zonatandem

Thanks for the replies. Hopefully tomorrow we'll be able to work something out ($$$) on this Tosa we found. It's a beautiful bike...we'll let you know!

'da Yoopers.

The only thing I would do, as it is a secondhand unit, is get the wheels retrued and retensioned right from the start. In fact I do this this with all my wheels, even though they are built by a good wheel smith, after about 500 miles.

It's already been said, but the quality of the wheel build is what matters. A set of wheels with properly tensioned spokes will hold up to considerable use. Just be sure that you're not selling yourself short somewhere down the road if you think you may need 26" wheels instead.

Is there really a difference in durability on a tandem between 700c and 26" wheels? I mean, I've made a lot more 26" tacos than 700c ones on my single bikes... Granted, it's a question of the type of riding you do, but isn't that the case with tandems as well??

DrPete

Once again boils down to the build quality and the state the wheels are in NOW. In general a 26"wheel will be stronger, but a poor quality 26" will fall apart easier than a properly tensioned 700. My Tandem wheels are Pretty good. Hope bigun hubs, 36 straight gauge spokes and Mavic full down hill rims. They will take everything that gets in the way of them on the trails, and are still good and true. However on the solo, xt hubs- 32 spokes on mavic 517 rims do have to be taken care of. There is no way that I would even contemplate a 700 wheel on our offroad, and that goes for the solo aswell.

Radial strength? All things being equal (rim design/strength, spoke thickness/swagging/lacking, and hub design), a 700c wheel is about as strong as a 26” wheel.

Lateral strength? All things being equal, a shorter wheel will be less prone to collapse when side loads are encountered, e.g., a 26” off-road wheel will be less likely to “taco” than a 29” wheel when it slams into a tree or rut and twists.

As someone else noted, a poorly built wheel that uses components that are not appropriate for the application will fail under heavy-duty use. Therefore, many marginal wheels “get by” without failure on ½ bikes that would quickly go out of true or fail when subjected to the increased loads associated with tandems; again, size doesn’t matter.

Some basics of wheel building: Deeper and wider rims are stronger than box section or narrow ones. Pre-stressed, swagged (aka. butted) spokes laced with higher than normal tension will usually outlast straight gauge spokes. Hubs designed for tandems will be more durable than those that weren’t. High flange hubs are stronger than low flange hubs and allow builders to use stronger lacing patterns. 40h and 48h wheels should use less spoke tension than wheels with fewer spokes.

So, back to the original premise that “all things being equal” produces wheels that have the same radial strength – which is what road wheels must primarily deal with – why do 26” wheels get the thumbs up on strength? Pretty basic… because 26” wheeled tandems have traditionally come with beefier rims that use high spoke counts AND have the added benefit of rolling on meatier touring tires that absorb road shock better than skinny, high-pressure racing tires.

Therefore, if you want a bomb-proof set of road wheels, go for a wider and/or deeper-section rim (which also do a better job of managing rim heat than box section rims) using a proportionate number of spokes and crossings for a team’s given weight (e.g., 300lb racers = 36h laced 3x, 400lb sport riders = 40h laced 4x, 450lb touring team = 48h laced 5x), and a tandem-rated hub with the appropriate flange height for the lacing pattern (e.g., low-flange OK for 3x but not suitable for 5x).

Again, at the end of the day it’s having a wheel builder who knows which components to use for the intended application and team weight who has previously (and successfully) built wheels for tandems and who appreciates that higher than normal spoke tension (but not so high that it exceeds the rim's spoke bed strength) and pre-stressing spokes are critical for durability and long-term reliability. Moreover, as the owner, you can ensure your wheels stay durable and reliable by periodically verifying they are running round and true through the brake blocks or stays. Prompt attention to an out-of-true condition will greatly reduce the likelihood of a future spoke failure.

Once again, TandemGeek comes through with the mother of all answers! :beer: Thank you!