Hi, im not an expert but very very happy with new continental grandsport 32mm. They were about 18 quid each (half price) direct from Contis website. 

I messaged conti direct so knew they were fine for my tandem. 

BW Nick

The Duet is a 26" wheel tandem. There is a very good range of tyres in this rim diameter  (ISO/ETRO 559) and we find a width between 40mm and 47mm works well. We are using 42-559 Schwalbe Marathon Supremes on our two Thorn Adventures.  They are free running, relatively light and comfortable and the protection layer has worked 100% so far well over 3000km.  Of course we could get mutilple deflations on our next outing. It's a couple of years since I bought any and the current pricing is a bit of a shock but overall I think they are still good value. They are a road tyre but OK of dry ex-rail trails and the like with care. It's well worth checking out the full Schwalbe catalogue as they give a reasonable idea about relative suitability of each tyre with its class. Obviously the indications of speed, grip and so on only apply within each class so you can't compare a road (race) tyre to an urban/touring tyre directly.

On the safety side, one of the problems you can get on a tandem rear wheel is the rim hook chafing the tyre.  If this isn't noticed in time the tyre splits just beside the bead and there is a loud band and sudden total loss of pressure. In our experiecnceI high quality tyres with a kevlar bead, light weight side wall and a separate chafer strip are better than heavy side wall tyres with thicker but unprotected carcass threads. It is worth checking the hook when you fit a new tyres as heavy carcass threads can cut into the alloy hook to produce a serated surface that accelerates the chafing. We have lost a couple of wire bead basic Schwalbe Marathons (the old kevlar type) to this kind of chafing damage but we are using up a set on our Dawes with regular checks for damage and keeping the tyre pressure right up to maximum.

Many thanks Nick and Martyn 

i have been looking at Schwalbe Marathon Duremes which are priduced as a tough touring tyre and have a high loading and are recommended for tandems.The info about the beads etc is very helpful,a sudden deflation could be pretty hairy. 

Bit more homework needed!

Schwalbe Marathons are excellent IMO, not the fastest but reliable. 

Seconded on the Schwalbe Marathons. A bit heavy but that doesn;t really matter on a tandem. Very reliable, virtually puncture-proof. I use them on our tandem and my commuter which sees about 5000 miles a year. Highly recommended.

Thanks Chris and Jon,settled on the matathons,next project a trailer to transport her about!

Cheers.

Mick.

Hi Martyn, what in the world is a rim hook?

I'm going to have my tyres filled with foam, I'll let you know how it works out once we've tried it for a few weeks. Most of my forestry equipment has foam filled tyres, it's not foam by any stretch of the imagination it's more like good quality silicone sealant, the best bit of it is that no matter how bad the tyre is it will not fail, it just needs to hold air when it's first filled, there is obviously a weight increase but I'll weigh the tyres before and after.