Vincent, Pauline's brother is taking care of an association for some rare disease that one of his friend's child is suffering from; this is is called Neurofibromatosis.
You can find details about this association on their FB:
Pauline actually helped them to translate their blog and FB into german. This was done for an event they have organized where Pascal ran from Rumilly in France to Michelstadt in Germany.
So our week-end started with a very difficult waking-up on saturday morning for me and a very fast drive from Munich to Michelstadt to see Pascal arrive.
That was grand! So welcoming and such a nice city! On our way back to Munich the following 2 days we went to several villages and Wine festivals. We were actually surprised to see so many people on bikes. Like we were the only ones with a car...
Where are they coming from? Where do they go?
That part of Germany actually looks pretty nice to cycle...
After one night in the tent, we started to build up some ideas.. Pauline wanted for some time now to go cycling but not mountainbiking. I love mountainbike so cycling on a flat land is somehow annyoing for me...
But... cycling for some days with the tent going along some rivers and to some places you don't understand the people.. Well that looks like an intersting thought.....
So back to Munich I switch on the PC and try to connect to the internet...
What I have in mind is some sort of a tandem where you somehow lay on the bike.. I will soon learn that this is called a recumbent bike... what a strange name for a bike...
After some searching it seems I have found what I was looking for! The Greenspeed GTT:
Wow that looks great!!! I found this webpage pretty good:
But then I soon got a bit discouraged by how much money I should spend to get such a bike... some thousand euros.. more in the range of 5000 euros... This is way too much ;(
Well here are some links I found interesting on the Trike tandems as we should call them:
There are several types of tandems like this...
Ok so Pauline is sleeping on the couch.. let's try to hide the price for a while a bring her some nice trip to do with that... So I went on searching what to do with such a bike...
I found that there are actually quite a lot of already organized routes for cycling throughout europe:
So there it is. I have found what kind of bike and some nice routes to travel to... now to convince Pauline!
In the back of my mind... how much will it cost to build it from scratch?
Well really this is way too expensive... and I think I know someone who will be interested and will tell me: let's build it.
You can call it providence but then 1h later the doorbell rang.. and guess who? Olivier and Marlene just back from 10 days of mountainbike in Corsica!
Just the right guy for this kind of idea!!
I just opened my mouth for 10 seconds then showed the picture of the Greenspeed GTT... and then everything started to boil in Olivier's mind!
What material should we use? steel or aluminium?
What kind of steering? should the 2 wheels be at the back or at the front?
How can we adjust the seats to different sizes?
How strong should it be to hold 2 people?
Can we rent such bikes to see how it really looks?
imagine what my dreams were made of.... ;O))
I thought about the gears.. and also looked at how complicated the chain connection gets between both cranksets... wow... it's gonna be tough...
then I thought about this:
Here are some more details:
I think with this we can spare having a rear derailleur with a cassette and complicated chain mechanism... this is of course a bit more expensive but much more reliable...
ok now say we travel some kilometers... thousand or so to remote russia? will they have this as spare parts in case it fails?
How surprising to see 2 trikes in front of my work building!!!
Here are the pics:
It's raining so it's the right time to look what can be found on the internet...
Some concept trikes!
What is this Rohloff stuff about? speedhub??
A very nice presentation from the Rohloff website:
Baically here are pros and cons I can see:
-More expensive than a standard hub system with front and rear gears like MTB
-Need a 'worn period' which means you need to make some kilometers with it before it gets optimal
-Need some maintenance? (not clear)
-Not a common thing to have. What if it breaks in the middle of Russia?
-Need some special spoke arrangement, but a tande, is anyway a bit special so that should not matter.
-System is meant to be mounted on a standard wheel. How to use it for a tricycle where it would be mounted on the rear 2 wheels?
-Does not need a front derailleur which for a tandem simplifies a lot the design
-Gears are evenly spread over the whole range. In case of Rohloff SPEEDHUB 500/14, you have 14 gears which you control from top to bottom with only one hand!
-No need for a rear derailleur so the ride height of the bike can be lowered which will improve aerodynamics.
Seems to be feasible... is it not overcomplicted??
Wide variation of trikes...
So we want to have 2 wheels at the back? (or at least that's my idea) but we see many designs with the rear wheels not vertical...
This is called camber angle... it took me quite some time to find out the technical term... here it is:
So it seems it give more stability to the trike when it's turning. Interesting feature it seems even though it complicates the overall design of the rear train.
As I was trying to understand this camber angle stuff i tried to figure out how the transmission could look like...
Basically the wheel axle will not be aligned with the crankset... so putting a chain in between might be a bit difficult...
Maybe it will be easier with a belt drive:
Well many disadvantages...
You cannot easily control the length.. so if we want to adjust the dimensions of the bike (for different people) then it won't work..
Furthermore you cannot open the belt.. so you need special type of frame:
?? what is this...
well imagine you're pedalling a lot and get tired.. you want to have a rest so you stop pedalling... should the other one stop pedalling as well for you to relax??
Now what if we are going downhill and both want to relax?
Again the one that wants to stop pedalling can be in front or at the rear...
sounds complicated.. but some found a solution... I think there are some better solutions!
A tandem from Sun has an Independant Pedaling System (IPS):
details of the system is yet to be understood... I think there exist freewheels that can be put directly on the crankset...
Interesting french website: Ekopedia.
Describes the trike and compares the different types:
There's an interesting comparison of Tadpole/Delta and Python...
Wood could be an easy material to build from... well.. not really good for cycling...
Iron, steel, aluminium need some soldering expertise... especially aluminium which is very light but nearly impossible to make...
Light is carbon fibers, also this can be modeled as you wish. Is that hard to make?? will cost a little bit more of course but such a bike should be rather light, isn't it?
This guy seems to have some good expertise:
We are not alone!! many people are making their own bikes and there's even a fair close to us!
30th of March close to Stuttgart ;o))
utahtrikes.com => cheap and robust design . Un tel type de section doit être plus facile à souder!
Lattice frame. Arrière suspendu et cadre en treilli... Avec l´habillage qui va avec:
fiberglass: too flexible + risk to split in 2 parts for 3D frames
aluminium: 1/3 lighter than steel but also 1/3 weacker => bigger or thicker tubes and requires TIG (Tungsten Inert Gas) welding => tricky to weld
steel: arc welding is definitely not a good idea. The hight temperature will weacken the steel. Can be TIG (requires special steel alloys) or brazed. Last solution could be possible, with lugs (hard to make but stronger) of without (requires a perfect and solid joint!). Seems to be the best compromise.
Here is an expert´s opinion:
I wouldn't recommend an arc/stick welder unless you are a very experienced welder using heavy guage mild steel tubing. Most people aren't precise enough to do this. High grade steel alloy bicycle frame tubing would be damage by the excess heat spread from this type of welding. High quality hand made lugged chromemolly or manganesemolly steel frames were usually silver brazed or brass brazed together. Luggless frame were traditionally brazed together with prescisely mitered joints. Modern luggless frames are usually mig or tig welded in a production setting, but often still brazed together by small volume handbuilders. I personally prefer to use a gas torch when building frames, but that is a personal preference. It is slower but quieter and there is no arc involved. I also learned this way before the other methods, a long time ago. If i wanted to build an aluminium frame, I would tig weld it Even if I were to make a frame out of old waterpipe, I wouldn't stick weld it. I do use a stick welder to fabricate with thick rusty metal, properly prepared, when I want really good penetration. My opinion is based on experienced gleaned from working in a bike shop where we built high end custom racing, touring, track and tandem bicycle frames and all phases of bicycle repair, including replacing damaged frame tubes in frames built by other makers.