Folding Tandem for the train!

I have never been a serious cyclist, but have always had bikes. The elegance of simple efficient transport coupled with 'it’s good for you', not forgetting the environmental benefits, has always appealed.

Following a ski-ing mishap, my wife Sabrina's physio suggested that cycling would help her torn ligament, so the idea of getting a Tandem slowly evolved. A tandem could balance-up our mutual efforts - if one leg out of 4 did very little, it would not really matter.

As a youngster I was interested in veteran bicycles, and had owned an old heavy pre-war tandem, so I was not a tandem novice. 

We managed to buy a second-hand low-cost tandem.  'Low cost’, meaning that it uses standard wheels and parts.  This means that it would probably break or wear out quicker because it is carrying twice the average weight.   However, as occasional users, this has not been a problem.

We took this tandem on several trips to France,  with the technique of laying the tandem flat on the roof bars.

We don’t particularly like driving.  Trains seem far more relaxing and far more sociable, so we considered a folding tandem that we could take on the train.

We were at a musical event in Dolgellau, and noticed a very functional-looking tandem outside. It had expensive-looking frame couplings, so could be split and folded up.  We soon became friends with the owners and heard all about their epic trips spanning many months, so our idea of a brief trip to France seemed possible.

When we looked at available tandems, there seemed to be either expensive or low-cost options, with little in between.  Given we are 'not serious' cyclists, and we were not sure how much we would use a folding tandem, I was erring on the side of low-cost.

We looked at the Ecosmo 20” wheel folding tandem.  At the time, it was £300...  How can they make a good tandem for £300?!, so various things went through my mind...  the unfairness of cheap labour in poor countries, the thought that this bike must be far inferior to our friends and others tandems.

After much deliberation we decided to buy this tandem with the expectation of spending a bit on modification, and also acknowledging that we would need to be very gentle with it.

So, here we are with a low cost 20” wheel tandem, not knowing if we had wasted our money or not.

I only discovered after the purchase that the chain wheels had independent freewheels in them.. i.e. either of us could stop pedalling independently. This also meant we could become out of sync.

Our initial ride on it heightened our confidence.  The free-wheel pedals we no problem at all, and we could see some advantages.  The steering was good, a little different from our other large-wheeled version, but it felt quite sure-footed.  The other worry was the need to remove the chain before folding it, however, this is a quick and easy operation, and not messy once a technique is mastered.

Having taken it out on several day trips, we decided to plan a trip with by train to France from mid-Wales.  This focused my mind on modifications.

The gearing   
The bike came with Shimano 7 speed derailleur gears.  The rear sprocket block was 14 – 28 teeth, meaning that top gear was only twice that of bottom – top gear was too low, and bottom gear too high.   I quickly learnt the difference between 'freewheel' and 'cassette' gears, and bought a second hand 'cassette' hub and new sprocket via Ebay, with teeth ranging from 11 to 32 teeth. (the chainset is 44 teeth).  By luck the ratios proved to be perfect for us – 32 is nice and low for steep inclines (though we do our best to avoid hills!).   Top gear is good enough since we never go very fast and pedal at the same time.  I am also mindful that this 11 tooth cog is quite small, so 2 people driving the one rear cog could be asking for trouble.....   we never pedal that hard!!

Brakes

Given that this tandem has standard rim brakes, and potentially twice the weight,  I was a little worried about the 20” rims overheating down a long hill. In fact I had heard 1st hand of brake failure on a tandem.  I looked into disc brakes, and so bought a new front hub and disk. I used an on-line spoke calculator and got my head around 2-cross and 3-cross lacing allowing use of the original spokes.  I spent a long time in a bike shop with an espionage hat on and took various measurements.  I rejected any bolt-on disc calliper holders and chose to silver solder on a lug to bolt the brake to.   It’s excellent!  Much nicer to have a brake that can be relied upon.  I guess I could have put the disc on the back since I changed that hub with the gearing. I think one disc on either wheel would have done for us.  
Note; brazing and the right silver solder is strong. Other solders are inherently weak.

We then found out a bit about the facilities that trains have for taking bikes.  Some hang, some stay horizontal.    The next mod was to work out a way of standing the folded bike in a vertical position.   When folded, the rear handlebars come off, so I managed to silver-solder on a pipe and clamp so that the bars could become a tripod with the seat.   This proved to work well, and was a necessity when the bike needed to be upright as on some of the French trains.

Above, showing handlebars forming tripod stand

Left, close-ups of pipe stub (could be old seat clamp) that I silver soldered on to the frame


Trailer
I then got to thinking about carrying luggage.  We had decided on the luxury of B&B (unlike our stoic friends who camp!), so we should not need a great deal of luggage. However, any extra weight on the wheels could cause problems, so I decided to make a little trailer.  It wanted to be narrow, so I based it around on medium-small suitcase on its edge.   I managed to find an old pushchair with nice wheels, and set about silver-soldering up a frame to fit the suit case.  I managed to make the frame so it could be taken apart very quickly, leaving 2 items for the train: 1) The folded tandem and trailer in one manageable piece, 2) the suitcase.    It proved to work really well. The folded Tandem was easily wheeled along and easily carried into the train.

The Tandem with trailer stowed away on various trains

Summary of the Ecosmo folding tandem.

As supplied, it is perfectly adequate for short distance cycling if it’s not too hilly.  It’s small enough to fit in most cars.. even small cars  It’s quick and easy to fold.   We reckon we can fold or unfold in about 4 minutes, but when fully loaded with the trailer, this extends to around 6 minutes.

It does however have limited gearing.   Fitting wide-ratio gears (probably needing a new rear hub) is not as hard as it sounds.  We found this mod vital.   The original fitments were Shimano, so good-enough quality.

The brakes are fine, but if you found yourself  loaded up at the top of a hill, you might be wishing you had a disc.  I guess either a front or a rear disc brake would suffice.  Our 160mm one works fine.

The tripod mod (using rear handlebars) is another worthwhile feature for certain trains.    

A seat clamp sawn off an old bike frame could be used. This operation is quite tricky. Time is needed to make sure the position is exactly right

Other mods I have yet to do;

A steering clamp (as fitted to some veteran bikes) would be handy for leaning the bike up. It simply makes the bars stiff from turning.

A proper clip to hold the bike in the folded position would be better than using the provided Velcro belt, or using a bungee cord.

Other than that, I cannot think of any mods

What might break?   This bike is not really designed to do very high mileage, and a few little details seem slightly suspect.  The easy-to-use clips that hold the folding clamps seem a little ‘light’, but if they need attention in the future, this should be relatively easy to remedy.

Message to Ecosmo, - I think the bike would look more aesthetically pleasing if the two crossbars met at the same level in the middle.  Oh, and if you are listening.... well done...  good design.

I am hard to please, and have an engineer's attitude – "look for problems and try to fix them".  I know that my wife is surprised that I'm not more critical of the bike, so it must be good!    If you do buy one though, I suggest that you allot some funds for improvements, and treat it with care.

I did actually spend 20 mins wondering about battery-assisting it. You can get a 20" electric hub.. could even push from a trailer.   I then realised that this was a daft idea.  The simple answer is... don't go quite so far, and allow time for plenty of coffee stops! 

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It's now 2023, and after much dithering and thought, we have gone electric!  We did wonder if it would be a slippery slope, but it does mean we can go further & faster uphill.  On the comments below you will read a lot of very excellent useful info about others (Mainly Shrimpy, Dod and others) who have also fitted an electric front hub.  

For us, only 250w front hub seemed the obvious choice. We only want 'assistance', and actually, we very rarely use top-power (level 5).    We went for a Yose system. Partly chosen because we liked the battery shape that easily removes for charging.  All electric hubs look the same, but build-quality no doubt varies. I have seen a poor quality one, and possibly/probably the Swytch (as Shrimpy describes) is better than our Yose... I don't know. It was nice that it has a disc brake flange.  Anyhow. the various electric cables plugs and sockets all look good quality.

When we first tried it, I initially didn't really like the noise.. It's no longer silent, and if we are in peaceful country, the slight whine is a little unwelcome, but that is very subjective.  It's put the weight of the bike up, and as yet, have not done a train trip, but I think we would manage OK.
Charging power is very small, and as yet, not had to charge away from home, but wonder if that could be slightly problematic finding a useable plug.  It seems to use 90W of mains power, so say about 3.5p/hr at present. 
Anyhow, a few pictures.   I spent a bit of time with some white paint.....  It makes people smile :)