Paul´s flevoproject

Rakennatko omaa nojapyörää? Täältä voit saada vinkkejä projektiisi.
paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Pastori

Thanks.

Paul

So many bikes to cut up and so little time .......

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Rainy day so a garage day 👍:LOL:

Kuva

Got front end fully welded , not cleaned welds yet [ may not ]

So sat horizontal , almost hit 45' with tube down to pivot.

Kuva

So rod projecting pivot to wheel contact patch.

Kuva

Where I almost nailed 0 inch/cm trail.......

Kuva

So said this was to be quick and very dirty !

Rescued a defunct MBB trike rear end from garage loft , disc brake rear wheels will stay.

For my inside leg front of seat ends up to the rear of block sat on frame.

Rear needs flipping over and shortening to about 26" track and front needs chopping off.

Then a pivot for tilting wants adding to the rear frame front and a piece making to mount the seat and joint the 2 pivots together .....

Not much if you say it fast Paul

So many bikes to cut up and so little time .......

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Ok more cutting .....

So we have this so far , still needs loads of welding

Kuva

Planned seat height will be about 19" [482mm] pedal height 25" [635mm] I am happy with that.

Front of seat frame will obviously be pivoted on pink BB.

Rear frame spar [ currently to long ] is about 5" [127mm] from ground , tilt pivot mounted somewhere on that spar with pivot axis pointing to front wheel contact patch.

Rear of seat frame fastened to other side of tilt pivot.

No suspension planned , this is a very quick prototype.

So w/b is mocked up @ 40"

Kuva

Track is a mere 23" giving about 18" of luggage width...

Kuva

Here it is next to prototype No1

Kuva

A little bit shorter and will be lot's higher !
Paul

So many bikes to cut up and so little time .......

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Vilijami
Pistosuojattu sisällöntuottaja
Viestit: 7072
Liittynyt: 27 Maalis 2014, 09:19
Paikkakunta: Oulu

Re: Paul´s flevoproject

Viesti Kirjoittaja Vilijami »

The picture shows that you have long (170mm) cranks.
:D In nojapyöräfoorumi we have subdivision "church of the short cranks" and we have a mission to spread the gospel of short cranks. :D (don't take this really seriously)
You reach the pedals easily and many other benefits. :wink:
Kids bikes have a 120-150mm cranks.

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Vilijami kirjoitti: 09 Touko 2021, 17:35

The picture shows that you have long (170mm) cranks.
:D In nojapyöräfoorumi we have subdivision "church of the short cranks" and we have a mission to spread the gospel of short cranks. :D (don't take this really seriously)
You reach the pedals easily and many other benefits. :wink:
Kids bikes have a 120-150mm cranks.

Vilijami

I to have some ' proper ' ICE trikes ' short cranks , several kid's sets and the taps to DIY my own.

However I just never seem to find the time to try them out :D

Always dashing off on some important project , like starting this one when I have not done any serious miles on the Flevo/Python hybrid I built on my last dash :wink:

Paul

So many bikes to cut up and so little time .......

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

This project has been put on hold for a while , as I sort of the handling of the prototype I made [ the one at the back ]:-

Kuva

I am struggling to guide it with my feet only and do not feel safe when on a path only 30cm wider than the trike and 60km+ traffic alongside me.
I am getting better at riding it however I seem to have a few ' tilt ' when not needed moments and a couple of why is it going in that direction moments.
I have probably done less than 60km on it so far.

I have 2 elastomers and have increased their stiffness however I have not ridden it very far yet.

What was the reason to get Zero trail for the tilting pivot ?

I wonder whether to try and get the prototype to have Zero tilt trail ?

regards Paul

So many bikes to cut up and so little time .......

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Vilijami
Pistosuojattu sisällöntuottaja
Viestit: 7072
Liittynyt: 27 Maalis 2014, 09:19
Paikkakunta: Oulu

Re: Paul´s flevoproject

Viesti Kirjoittaja Vilijami »

paul_n kirjoitti: 11 Kesä 2021, 19:25

What was the reason to get Zero trail for the tilting pivot ?

Negative trail is like a ball in a valley. Good to very slow speed. Hard mass centralize.
Positive trail is like a ball on a top of hill. Good to very high speed, when centrifugal force beats the tilting mass.
Zero trail is neutral, ball on flat. Not react to speed.
Just same think, steering or tilting.

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Ok thanks for the explanation , Zero tilt trail equals neutral handling and does not change as speed does.

Kuva

Looks tricky to implement on the prototype ?

Paul

So many bikes to cut up and so little time .......

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Vilijami
Pistosuojattu sisällöntuottaja
Viestit: 7072
Liittynyt: 27 Maalis 2014, 09:19
Paikkakunta: Oulu

Re: Paul´s flevoproject

Viesti Kirjoittaja Vilijami »

Drop the balljoint down as much as need.

Liitteet
FD689618-61BE-4575-BE02-65F43813494D.jpeg
paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Well I have ridden my prototype again to test some changes I made ?

When I first built it I added a second damper to reduce the yaw I was getting from only having one elastomer and the rod end giving 3 axis of rotation ?

So rode with 2 x 84 kg so 168 kg resisting the tilting [ the value is the compression value no one seems to quote bending values ? ]

However I have now upped them to one @ 113 kg and one @ 203 kg so now 316 kg resisting the tilting
An increase of around 45% to it's stiffness.

I find the trike much more restful to ride , stiffer and it feels to accelerate the tilt less when it has started ?
It still swoops and carves the corners as I want so seems just as agile.

However I seem to remember a post on here which started out adding stiffness to the tilt and eventually removing all springs/elastomers so no tilt damping at all ?

What was the reason for that ?

I think apart for a small snagging list I will now just ride the prototype as seat time is very important to master this ? i.e I can safely ride one handed but not no handed [ a useful skill on the Python ] , and resume the Flevotrike I started.

I was puzzled to find I can also tilt & un-tilt with the hips and not as I initially thought moving the shoulders ?

thanks for your input Paul

So many bikes to cut up and so little time .......

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Vilijami
Pistosuojattu sisällöntuottaja
Viestit: 7072
Liittynyt: 27 Maalis 2014, 09:19
Paikkakunta: Oulu

Re: Paul´s flevoproject

Viesti Kirjoittaja Vilijami »

paul_n kirjoitti: 16 Kesä 2021, 17:53

However I seem to remember a post on here which started out adding stiffness to the tilt and eventually removing all springs/elastomers so no tilt damping at all ?

What was the reason for that ?

I think apart for a small snagging list I will now just ride the prototype as seat time is very important to master this ? i.e I can safely ride one handed but not no handed [ a useful skill on the Python ] , and resume the Flevotrike I started.

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.

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Vilijami

When it is so easy to just bolt a Python front end to a bracket and ' make ' a trike it is tempting to build lot's ?
So I am also tinkering with this ?

An iLean rear end ? I have now got the beggar to stand now unaided !

Kuva

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.

Kuva

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

So I can compare it with my Flevo inspired prototype ?
It should also give a sort of suspension as it halves the height of bumps.

regards Paul

So many bikes to cut up and so little time .......

Avatar
Vilijami
Pistosuojattu sisällöntuottaja
Viestit: 7072
Liittynyt: 27 Maalis 2014, 09:19
Paikkakunta: Oulu

Re: Paul´s flevoproject

Viesti Kirjoittaja Vilijami »

There is still very little experience of that ilean axle here on the nojapyöräfoorumi.
Make many different back ends, but remember 1000km each…. :wink:

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Vilijami kirjoitti: 17 Kesä 2021, 11:43

Make many different back ends, but remember 1000km each…. :wink:

You tease , that is about 2 years cycling , unless I have a 2 week holiday in Holland :mrgreen:

Paul

So many bikes to cut up and so little time .......

paul_n
Viestit: 39
Liittynyt: 09 Kesä 2020, 12:20
Paikkakunta: Mansfield - United Kingdom

Re: Paul´s flevoproject

Viesti Kirjoittaja paul_n »

Vilijami

Negative trail is like a ball in a valley. Good to very slow speed. Hard mass centralize.
Positive trail is like a ball on a top of hill. Good to very high speed, when centrifugal force beats the tilting mass.
Zero trail is neutral, ball on flat. Not react to speed.

Having read this a good few times I am not sure it is right ?

My take on it ?

Positive and negative trail are the same thing , on a steering wheel the axle either in front or behind the steering axis and if the correct value of trail results they are both ' ball in a valley '

Zero trail is neutral , ball on the flat.

Now this removes speed from your explanation , however is speed relevant if talking about tilt ?

So my question is there an effect I might see from infinite tilt trail , or is it likely it is masked by the sheer mass of the Python front end ?
It is over engineered as I could not find the right steel at the time it was built , so the front end probably represents 60% [ or more ] of the mass of the trike .

The iLean was a dead end , still a 2 wheeled Python with very bad habits , that I have no intention of learning to ride.

So more Flevo development :D

Do you have any view of the height of the tilt pivot from the ground ?
I have the dilemma of wanting a higher seat than the current prototype so how do I get handle bars on the non-tilting bit if the pivot is 15cm from the ground and the seat is nearer 50cm ?

regards Paul

So many bikes to cut up and so little time .......

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