My life with Python trikes Mk1 , Mk1.5 , Mk2 ?

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You can ad mounting points for elastimers to the middle part on both sides.
The closer you put them to the center, the more movement in tilt you will have. They will limit the tilt, but you can play with that, by using harder or softer elastimers and with the distance to the center.
Sadly this was not designed for elastomers and so fitting them is problematic , however there are always other solutions to these problems.....

Watch this space....

I have an appointment with a welding machine .....

Paul
 
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Ok so we have some answers ?



You can just see the repair to the square tube to align the two BB's , here the pedal crank arms have been locked to align the tapers on the BB axles whilst I weld the central tube connecting them.
The central tube can be removed by taking a BB axle out and pulling it off the other axle.
I do need to re-grease the BB's as some grease was burned off during the welding.

So first question is can a 25.5" track iLean stand on it's own 2 wheels ...



Err ,,,,,,, NO !
it does not actually fall completely over , probably because it has no weight driving it i.e the front end or seat or luggage.
However it does tilt quite a long way hence being propped up with ' stuff'

So what elastomer's do we have to try ?



This would be the best elastomer to use as it will bend through 90' and I have 3 so could mount 1 or 2 or 3.
they would be hard to fit due to having threads both ends and if they regularly bent to 90' I suspect they would soon fail.



this would be easier to fit however it will severely limit the tilt available.

So we need to try an inner tube , watch this space...

and for Popshot and the mathematically curious ? how much tilt for :-

20" wheels - 140mm cranks and 25.5" track ?



sneaky not quite in focus 😂:whistle:



Did you guess right ?

I think what is alarming is the small measured angle against the huge visual tilt ?

Can see riding it with tilts of between 30' & 40' ? can you ?

ain't it great when us shed tinkers can be on the leading edge of bicycle design just by getting out of bed on a morning ....

Paul
 
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So hoping to take this for a run tomorrow , nice ride into the forest maybe weather permitting ?



been contemplating the next move to get the tilt axis aligned closer to this ?

Now being a bolt together concoction it is possible to bolt it together in other configurations ?

If the rear end is reversed and the lower frame bolted back in place it looks like this ?



So ignore the upper part with the seat for the time being , if the lower frame was then just angled down so the rod end tilt axle pointed at a spot 40" in front of the rear wheel centre [ in other words a 40" track ] then we would achieve zero tilt rail ?

It would leave a couple of problems to solve ?
  1. mounting the rod end at right angles to the blue line and the 2 elastomer's would need a mounting and it would have to be of such a shape the seat ended up with the correct back rest angle ?
  2. the Python front end pivot would be way to high and the pedals much lower ? maybe level with the bottom of the seat ?
The pivot could be fixed by a extension to the mount moving the 12mm mounting bolts lower , messy but could work.
The pedals could be raised a couple of inch's by cutting and shutting the front frame just in front of the drop outs ?

This whole exercise would also raise the seat , one of the goals of the project :LOL:👍

Warming to the idea...

Paul
 
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So you want to angle the tilt like in the first photo, but than angled like the blue line.

As you tilt then, you also steer a bit, or you need to counter steer.
 
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I think that it will mot be a big problem and that it only needs a tiny bit of counter steer on angled roads.
As least you sit straight and not under an angle.
 
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I think that it will mot be a big problem and that it only needs a tiny bit of counter steer on angled roads.
I suspect it already does that , just to small to notice , with all that weight/bulk on the front small things like that that get lost ?

As least you sit straight and not under an angle.
yes I have seen that , even just not sitting in the middle of the seat causes the front end to tilt over whilst still going straight , try that on a lean steer 😁:whistle:

Paul
 
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Ok well the beggar stands now unaided !



The left hand clamp holds one end of a duff 20" inner tube it is then wrapped around the centre axle of the ilean and back around the square frame until I run out of inner tube and axle.
Each turn was pulled tight and it was held by the far right clamp.



The central clamp fastens the ilean rear end onto the old Python spine and the thing is free standing and level !

Although it is wrapped around the ilean axle it is not really directly acting on it so it does not self-centre well however it does slow down it's movement and allow it to free stand on it's own ?

To get it to self centre one idea would be to add a bar welded to the ilean axle tube to directly wrap around it so the bar deflects the rubber rather than the friction connection it currently has ?

However I have noticed a rather disturbing trait ?

When manouvering via the Python spine it cannot be turned easily I suspect because the wheel axles are staggered it seems to drag one wheel and resist turning.

Will it be like that when riding it ? or will the turns be large enough not to notice ?

I think some of the bike implementations have really small pedal cranks maybe even sub 100mm [ uni cycle I think ] maybe to reduce tyre scrub ?

I will work on it to get rid of the clamps and look at mounting it onto the spine in preparation for a ridable trike

Paul
 
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Now it is testing what works for you with the inner tube.
I wouldn't go yo extreem, because then it is harder to tilt.
 
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Got a good social ride today on the prototype :-



I rode to S-in-A looking to see if a shop had survived the pandemic ? after that the first port of call was Sutton Lawns , this is the trike parked by their lake , it is fed by a spring and is the source of the river Maun that gives Mansfield it's name.



I mainly followed the river which is very small some times only 6ft wide and 2ft deep sometimes 14ft wide and inches deep , however it is very important to Mansfield. At one time there were 7 water mills on it and the Duke of Portland managed it as water meadows damming and saving the water to use on his fields in the past there were mile upon mile of meadows and people employed full time to manage the water.
This is one of the few remaining mill ponds the path is quite hairy at times it is tarmac however it slopes quite steeply across it's width towards the river and is slippery with moss and fallen leaves , to add a frisson of excitement to the ride the river is sometimes only feet from the path although it can be between 1ft and 15ft below the path !



The destination Tichfield Tea house for breakfast....



And the view from my table.

So first ride with stiffer tilt damping ? so how did it go ....

Awesome ! much more in control just 2 incidents both really old f*rt brain freeze really and not dangerous just frustrating.
a) hit a lumpy patch and trike lurched from side to side leaving it with a small tilt to the right - brain froze and was slow to correct it.
b) gears seem to skip a cog over a bump and became very noisy I had no idea what had happened so had to stop and look - if chain was not touching frame there would have been no problem

Stiffer tilt does not stop it swooping and carving up corners , however i think it stops the feeling the tilt is acceleration when it is initiated , it also stopped most of the ' unexpected tilts ' I also found it was easier to get through those pedestrian barriers as it was slower to tilt or resisted my inappropriate tilt actions.

I discovered tilting is NOT initiated by moving my shoulders when gripping the non moving bars ?
Tilting from me seems to be initiated by moving my hips ? I assume braced against my legs , this may account for some of the strange behaviour as steering is also the hips !
I think rocking the hips from side to side causes tilt and swiveling the hips front to back causes steering.

I can now ride one handed without any problems however I cannot ride no handed yet [ can on normal Python ]

The Finn's suggest NO dampers on tilting so I asked why ?

The first i need elastomer/springs when i learn to ride my tilting Flevo trike. But later when my ride skills improved elastomer/springs started hamper handling, especially high speeds.

Remember give a time and kilometers. 1000km is absolute minimum before final opinion.
I am sure, than you learn to ride without hands. Certainly.


So only about 922 km short :whistle:

I had already come to the conclusion I will not butcher the prototype any further ? and get some miles on it
I have a small snagging list to attend to :-
Crank up front of frame to raise pedals and help chain clear frame.
Fix parking brake
Make handle bars longer and mount a little wider.
Fix rear end permanently
Improve seat mount and make seat a little higher
maybe reduce track a little , mainly to improve rear wheel fixing as they are way out of tracking 0'

So looking good and riding is getting easier.
paul
 
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Looking like it's becoming a success story through perseverance.
I do see it as a collaboration , there has been a lot of positive input from this forum and the Finn's :D(y)

Paul
 
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Paul, look ad this one.


He has more videos on his channel, showing the trike and also more of the construction.
He rides without hands without a problem.

Now was i comparing that one with your trike, **** his one and with some other ones.
I noticed 2 differences.
The first one, I can see on all I found and that is that the tilt system is above the center of the wheels.
I didn't see one with it below it. It is possible that there are, but I didn't see one.
The second thing I noticed, was the angle of the tilt system. Clearly visible on this trike, but I have seen it on some others also. I don't know if it matters, but where possible, I see that they all are angled backwards a bit.

After watching and thinking. I think that the angle comes by how they create the hight and that the small angle, has no effect on keeping balance.

The height is an other thing.
Here is what I thought ad first. The distance between the tilt and the seat stays the same, no mater how high you set it and therefor, that it doesn't matter if you make a low rider or not.
But that is changing after watching the video several times. I think that the front wheel has influence on the tilt and that as you raise the tilt above the center of of the wheels/ front-wheel.

I can be wrong and that it is still a balance thing and that the front wheel has no effect on it. But it is something you can try.
 
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Maybe I am wrong Paul, because I see that many people have problems riding on a flevo bike for the first time.
But for what I see it is harder on a 2 wheeler, than on a 3 wheeler.

Just my thoughts. Let me know what you think about the height and if you think it would matter.
 
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Emiel

The Flevobike/trike is a poor design that you can learn to live with , if I was on main land Europe I would have bought one to tinker with I suspect there are as many languishing in sheds un-ridden as there are in use !

My design is severely compromised by using existing Python front ends and geometry.

My aim is for a taller trike with a seat height between 18" & 20" [ 45cm - 50cm ] and narrower rear track down from 30" to around 26" [ 76cm to 66cm ] hence looking like a Flevo bike/trike.

I have started this :-



Which as you can see has a much higher pivot and pedals , it was paused as I was unsure of the handling of the current tilter.
Now the current tilter seems to be sorted I will continue with it and see where we go.

Paul

ps of course you could also build one and supply ME with the answer ?
 
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I am not flexible enough to ride it.
Is that why you are making the camping trailer rather than a tent ?


In that style, I love the looks of the mosquito.
Can you get down that low ?

Paul
 
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Don't quite think it meets the criterion of languishing in a shed ?

Would you attack it with an angle grinder to sort out it's troubles ?

Paul
If you buy it, I promise you I will help chop it up with an angry-grinder.
:)
 
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