Our new tandem bike

Bicycle is the best way of transportation and travelling as a couple is better then alone. How have we got the idea of having just one bicycle, but not a classic tandem…

Somewhere in South America we saw in one guest book a photo of a “weird” bike with 2 people on it – the front one laying, the rear like on a normal bicycle. This “thing” stayed in our minds because doesn’t have the main disadvantage of a tandem bike – that the rear person looks always at the back of the front one.

We came back and we got to know Honza from AZUB. He is a recumbent-bike fan so his first reaction was that it’s a bullshit because we will fight for the front spot. At the same time he mentioned that they’ve already built something like it.

Year later we decided that we really want this bicycle. There aren’t many options on the market and all of them are expensive:

We’ve browsed the net and tried to find as much information as possible (e.g. on cyclingabout.com is a good summary article with more links) and at the end it was clear that we will not buy anything for 5000€ which we haven’t tried and also because these bikes have also problems (for example a frame breakage!).

We contacted AZUB (tandemservis), who’ve build bike like that. Almost everything was arranged, components and color chosen we only had to pay the deposit… and the we found and apartment in BB. Evit was pregnant at that time, place to live was a priority and all our money went there…

Another year later we met a loaded touring cyclist Jimbo on the street and invited him to stay with us. He inspired us again for travelling and we decided to get our dream bike. AZUB had too much work and couldn’t build the bike till summer.

We didn’t know any other bicycle builder at that time and decided WE will build it – if it was possible to build bikes 100 years ago, an amateur can also weld a bicycle these days. I bought books (I recommend Mike Burrows: Bicycle Design, which really broadens the horizons), read articles on internet, watched videos about TIG welding, consulted friends…

To build a bicycle “at home” looked too difficult if not impossible, but then we heard about a guy who builds bicycles here in BB. Vlado liked our project and gave impression that everything is possible and they can finish the bike till summer.

We were happy – we found somebody with experiences welding bicycles and therefore we don’t need to calculate the steel strengths and bicycle related specialties in detail. We bought the front seat from AZUB and Honza gave us many good advices. We only needed to invent the frame – respectively integrate the ideas from existing bikes with ours to our perfect tandem :).

As the base we took the Hase Pino:

  • 26″ wheel in the back – strong and durable
  • 20″ wheel in the front – so the front seat isn’t too high
  • handlebars vertically at the shoulders of the front person – to shorten the length of bicycle

Inspiration for the rear construction was the legendary touring bicycle Surly Long Haul Trucker

  • bottom bracket drop 5cm – to lower the center of gravity
  • longer chainstay – to have enough space for pannier in the back

The angles of seat tube and head tube are with no doubt important and influence the character of the bicycle – but this project is so different that there wasn’t too much to compare with (only the Bilenky Viewpoint publishes the angles) so we decided to avoid extremes and put same 72° for seat tube, steering tube and fork (head tube).

For the front construction we chose simple and aesthetic solution with straight top tube. It was a prototype and we were not sure how will be the pedaling in the front so to be sure we put 2 options for mounting the pedals. We wanted to rent the bicycle to other people (shorter or taller) so the distance to the pedals has to be adjustable – we decided that adjustable will be the seat, which is mounted on all-purpose rails on the top of the tube – with possibility to mount also the handlebars, rack or a cargo rack like on the Circle Morpehus.

The whole length (cca 2.5m) was given by the length of the front part and the wheelbase was set more or less intuitively. We wanted to have also the possibility to fold the bike for easier transport in various vehicles.

The 20″ suspension forks for tandems actually don’t exist so we decided for a rigid fork with classical 4cm offset which was made also by Devilwork. The advantage was that directly on the fork was a mount for the steering rod.

Another specialty is a freewheel – the front person doesn’t need to pedal and can just enjoy the view. Hase and also the Tandemservis bike have this feature – the inspiration came from here.

First sketches:

skica2skica1skica3pohlad1

Final drawing:

nakres-final

Photo from a testing ride with a trailer (the grey color is the original color of the steel tubes – we still have to paint it):

foto s vozikom

So now after 5 months since the first sketches (2 months after deadline) we have our dream bike which has still some problems which wait to be solved – and some more will show up later while travelling. After couple of test rides we can say that the handling is really good and the feeling that we can talk to each other and the front one can just enjoy the country is perfect! And we even bring smiles and surprise to peoples’ faces when they see us riding 🙂

Now we are going on a 3-week test on the roads in Slovakia, Czech and Austria and we will share all the experiences and interesting stories with you! 🙂

5 Replies to “Our new tandem bike”

  1. This .. is totally amazing. You should come to Scotland – I know some good places to go, and I need some advice about trailers 😉

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