Does anyone here have any experience with 135 rear spacing?Max team weight will be 350lbs.

The reason it attracts me is I can use my 29 mtb wheels to have several sets of tire combos to swap out.I only mtb in the winter,so I could use those wheels in the summer on the tandem.

I think the chainline could be better with 135,maybe lower Q for the stoker,and more heel clearance.

I also know they will be weaker laterally,but maybe they will be strong enough.

Have a standard MTB 135 mm spaced rear wheel with 26" rim on our tandem. No problems to date, including much hill climbing and mriding on mountain roads. Haven't taken the tandem off road, but don't see any issues.

do you have a dished rear wheel? what hub/rim/spoke set up are you using? also, what rear brake setup?

Road Bikes: If you go back in time you'll find that most tandems used standard road bike rear wheel spacing as there weren't any wider options. Consequently, very heavy touring rims with lots of spokes became the norm and wheel problems weren't all that unusual. Fast-forward to today, while we spec'd 145mm on our two tandems, we know folks who have had tandems built with narrow spacing to allow for use of standard road bike and time trial wheels. These folks are all fairly lightweight teams who race and understand the limitations and increased wear and tear that a tandem will put on wheels not specifically built for clydesdale / tandem weights. So, in answer to your question, "could you use 135mm"? Sure, but if you did I'd suggest you use a 48h high-flange hub like a Phil Wood FSC and a deep section rim like a Velocity Deep-V with the rear wheel laced 5x.

Off-Road Bikes: FWIW, 135mm rear spacing isn't all that unusual for off-road tandems, noting that 26" MTB wheelsets are inherently stronger than a similarly constructed 700c wheel. Unless a customer specifies 145mm rear spacing, all of Ventana's El Conquistador de Montanas tandems come with 135mm rear spacing and rear disc brakes. Therefore, rear bracing angles are no different than they are on any other 135mm mountain bike. We've been able to get away with using 36h spoked wheelsets on both of our last two Ventana's and have never had any problelms: our current '02 model has 36h Chris King hubs with Velocity Aeroheat AT rims and 4-pot Hope Enduro disc brakes. Then again, we're also a fairly lightweight team. However, many of he teams we ride with aren't and I don't believe they've had any problems when well-built wheels were used and kept up to snuff with respect to trueness and tension.

I built up a set of 700c disk wheels for my tandem using Shimano XT disk hubs (6 bolt style), with 36 spokes, 3 or 4x lace. Sun M13II rims

Early on I had some spoke breakage issues. But these were due to inferior spoke quality (same spokes broke on my single bike also).

I replaced those with DT Alpine III spokes, which has stopped the spoke breakage issue since I laced them up 1000 mi. ago.

I went with this setup because Shimano XT disc hubs were way more affordium than tandem specific disc hubs, and so far no problems with the hubs at all.

Rich

Team weight and gearing?

Team Weight: varies a little with my stokers. My gf & I have a team weight in the neighborhood of 300 lbs. Other stokette friends would probably be in that vicinity as well, or at least no more than 350 lbs.

Gearing: Shimano 9 spd., 12-32 in the back, I think. 52-42-30 in the front.

Can't remember the make of the rim or spoke set up and am away from base at the moment. Hubs are Shimano Deore, wheels will be dished to accept 9 speed block and Hope disc brake.

If you need futher details let me know and I'll check when back from Japan.

I was looking at 2 tandems in a local shop today-the first had a White Industries hub with a 6 bolt disc mount on it.The flange spacing is the same as a mtb,after a rough measurement with a ruler. There was a wide spacer to space out the 6 bolt mount.

I then saw a Shimano hub with a thread on for a drum brake and it also had similar spacing-around 50mm flange to flange.

These 2 hubs suggest that there is no reason to think that these wheels would be any stronger than a 135 mtb hub.

I don't know the flange spacing on other hubs.