I have my exquisite electric Pino on sale on eBay at the moment. Happy to cancel the listing for sensible offers. https://www.ebay.co.uk/itm/176417593233

If your current tandem suits I'd definitely go for conversion. Probably a rear hub, possibly a front hub or crank. Do ask lots of questions at
https://www.pedelecs.co.uk/forum/forums/conversion-kits-general-discussion.42/ before going ahead. Most of the problems there are from people who bought first and then asked the questions.

We converted a basic Viking tandem with front hub XF07 from Woosh. This has been a great success; good help on the flat and hills, but still leaving us with work to do. I'd have gone for a more powerful motor but no suitable legal one was available in 700c at the time we bought it.  The risk of loss of traction on a gravelly hill that applies on a regular bike does not matter nearly so much on a tandem with the different weight distribution. And better two wheel drive traction has often helped us on slippery slightly uphill grass, the rear wheel driven by us has slipped and the front motor has pulled us through. We are considering change, but only because the front crossbar is getting to be an issue as I get older. I'd recommend Woosh for excellent pre and post sales advice, especially for first time conversion.

Buying second hand ebikes beware the battery may well be shot, and expensive to replace. Especially if it has low mileage it may be that it has been allowed to sit at unsuitable charge (too high or too low) over long periods.

Tandems sold originally as ebikes almost always have proprietary electrics, typically Bosch or Shimano. These work well and are generally reliable, but things can get very expensive if anything does go wrong, and you'll very likely be tied to a dealer to get it fixed. Also, more expensive batteries. That said, we bought a second hand Motus (Bosch driven solo bike) and have been very satisfied.

@Bruce Devlin: I can't see how to do a private message here.

I've been searching ebay regularly and not seen your tandem. It is too expensive for us anyway, but I thought you should know that (for me at any rate) an ebay search for 'tandem' does not find your listing. Changing to 'tandem pino' does find it, but with most sort orders it is lost among irrelevant items (price decending gets it ok). That might mean you are missing potential buyers. Not sure how/if you can change the listing to correct that.

I agree with the comments made by Stephen Todd above.  The Pedelecs forum will give you a lot of information, but as with any internet forum you need to filter / interpret the more strongly expressed opinions!  I have posted my own experiences on Pedelecs:

https://www.pedelecs.co.uk/forum/threads/wooshing-along-on-a-dwg22c-%E2%80%93-3-000-miles-and-counting-%E2%80%A6.45644/

I’d not rush into a decision – take your time and do your research.  For example do you want:
Cadence control or torque sensing control
Current control or speed control
Sine wave controller or square wave controller
Mid-drive / front drive / hub drive (each has advantages & disadvantages)

The above points are slightly tongue in cheek as you don’t absolutely need to know these things, but understanding this sort of stuff will help you make a better decision.  If you really want to get into detail, have a look on the ‘Endless Sphere’ web-site.

I converted our Orbit tandem to a rear hub motor (DWG 22C kit from Woosh) and have been very happy with it.  I think it gives us about 95% of the functionality of a shop-bought machine at a fraction of the cost and it is easily (and cheaply) repairable.  The most obvious downside of a rear hub drive is that it makes fixing a flat tyre more involved (but Marathon Plus tyres solve that issue).  

Tandems are very hard on rear wheels, so after a few spoke breakages I rebuilt my wheel with a Ryde Sputnik rim using Sapim strong spokes.  The large size of the motor hub flanges mean that a single cross lacing pattern is the only sensible choice.  Having done this, I have not had problems over a few thousand miles now.

My main peeve about shop bought machines is that they are virtually unrepairable for the average person (and some dealers) – and very expensive too.  I could replace my entire motor wheel for less than £200.

Bottom line – going with electric assist is quite transformational.  You’ll use your tandem more and go further.  Do it!

We had a mid drive motor added to our Pino tandem 9 years ago (when we reached a joint age of 150).  It has been excellent for the first 10,000 miles, and has not affected the handling of the bike; when the motor is switched off we don't notice it is there.  Because it is a mid drive system we avoided the necessity of wheel rebuilding.  The batteries had to be replaced last year when they were down to 30% of their original capacity.  This reinforces the point made by Stephen that you should be cautious about buying second hand.  Because the battery sits on top of the rear pannier rack rather than within the frame we are not tied to a particular brand of battery.  Our new one is a Sparticle battery from Electric Transport Sales who say it has passed exhaustive safety testing.

Once you've added electrics you won't be able to take the tandem by air, unless you can rent a battery at your destination.  If you are thinking of doing overseas trips by air it is worth choosing a standard model of battery which might make this possible. 

Peter Mynors

We converted our Dawes Galaxy Twin with the Swytch Pro kit (currently for sale reasonable offers considered) and gave found it immensely helpful as far as power levels and range.

Hi, I converted our recumbent Nazca Quetzal tandem to e-assist with a kit using a 48v tongsheng mid-drive motor. This came with freewheeling crank, which I fitted to the captain's position and I also got a freewheeling crank for my stoker. Really nice kit and a great help for us both, especially as my stoker has needed some additional help pre and post knee replacement. The supplier I got it from has ceased trading but there are others who supply similar kits, e.g. electric-bike-conversions.co.uk

Cytronex is a good,lightweight system. It has a very low capacity battery, working on the assumption that to get any range the rider(s) will do most of the work. They don't specify torque but I suspect it is quite a bit below the XF07; and we'd want more rather than less on our tandem.  Quite expensive for what it is, especially given the battery capacity.

Swytch has quite varied customer satisfaction, a lot of negatives on the pedelecs site. Expensive unless you get their common 50% off offer; about a sensible price with the offer. Their marketing is what makes them so well known; their engineering isn't at the same level.

I definitely recommend Woosh (as in my earlier post), so do many others. Not the cheapest, but cheaper than the alternatives you have mentioned. I'd go for the bigger battery; not only longer range but less voltage sag under load, and probably longer life as with more cells in parallel each one is providing less current.

To add even more clarity / confusion to the mix - definitely go for a 48 volt system rather than 36 volt.  The extra 'oomph' of 48 volt makes quite a difference when fitted to a tandem.  I also recommend Woosh as a supplier.

A newer type of cell (21700) has appeared recently which provides more bang for your buck than the older 18650 type.  I don't think these are available yet for the Woosh hub kits unfortunately.

I can't find a way to send you a PM, but if admin can give you my email address, I'm happy to chat further on the phone / email if that helps.  If you are anywhere near me, you're welcome to have a test ride on my machine to try out a rear hub motor conversion.  Removing a motor rear wheel is certainly more hassle than a front, but it's really not all that bad.  I would not rule out choosing a rear drive on that basis alone.

Woosh also sell a 'beefed-up' Tongshen (TSDZ8) mid-drive kit which should suit tandem use rather well.  You'd need to watch the overall width of that unit though and I think the 'Q' factor is quite noticeable on the Tongshen.

If you go for a front wheel system, please check carefully that your front forks, especially the fork ends are suitably robust or that you employ some sort of torque arm. With the extra weight of trying to pull a tandem with two people on relying on the flats of a spindle to resist the resulting torque of a motor can be disastrous with the fork ends being opened out over time.

I to have a Cytronex system and would agree its ok for a solo but not enough power for a Tandem, we asked for a second battery but due to supply they would not sell us one , Had to take another route to power.!!

@Gillian: If you are anywhere near Winchester and would like to try our tandem with XF07 front you would be welcome. The bike itself is more basic than yours, but any test ride is much better than none.  (And you can visit Cytronex as well, less than a mile away.)

Many thanks to all for these replies.

Much useful information which we are taking on board and helping to hone our decision. I'm currently looking closely at the various offerings from Woosh and I've sent them a list of questions which I think will direct me towards a solution there. I'll let you all know how this project goes.

(As for the kind and generous offer of the test ride, many thanks but we live way over in East Anglia so a long haul,!)