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

Joined
Sep 16, 2018
Messages
1,077
Location
Netherlands
OK you now use the handle bars to make it easier to keep balance.

It looks good Paul. I hope to see it sometime and try it.
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
OK you now use the handle bars to make it easier to keep balance.
The bars are on the non-tilting part and so only hold the levers and allow me to control the tilt , steering is feet only.
I don't want to ride it like this as I feel unsafe riding it like that , currently it takes all my concentration and energy to keep it on my chosen course [ very tiring ]

I have tried the bars again briefly on the steering part and cannot launch myself with 100% confidence ?
You can put the right foot on the pedals and attempt to get the left foot up without realising the left foot is holding the whole shooting match vertical.
As soon as the left foot leaves the ground the whole front end falls either left or right before you have set off EVEN with both hands on the bars, most odd and unexpected.
Because of this I have not ridden it far enough to see if bars on the steering/tilting part are viable.

It looks good Paul. I hope to see it sometime and try it.
We are a long way from going to Holland on it !

I really want a tilting mechanism that is controlled by my weight and riding dynamics not having to control it by bracing myself against some bars on the fixed part of the trike.
I may try a Mosquito rear end bolted to a normal Python spine , or proceed with a iLean I have part assembled.

I have been reading lot's about tilting trikes with several people saying once on it you just think you are riding a 2 wheeler ...
Well oddly I realised mine does NOT feel like you are riding a 2 wheeler , just a Python trike with another axis of movement , not the same think at all.
I have never had a 'oh sh-t' 2 wheeler experience on it just a few 'oh sh-t' trike type moments most odd.

regards Paul
 
Joined
Sep 16, 2018
Messages
1,077
Location
Netherlands
Most use the system that DannyC uses. That will give more a feeling of a 2 wheeler.

I have several systems that I like for different reasons. The Mosquito in wood looks just great and I would love to build one in wood.

Then there is this one.
It is simple, but it works. It can be setup so the wheels tilt more or less.

I like Also the one that Popshot builds.

But as I now would build one, I would go for the wooden Mosquito. It just looks great and it is so different ad it is in wood.
The one in the video is a good second.
Maybe I use my first build, to make it cimilar to the one as in the video.
 
Joined
Oct 19, 2012
Messages
1,505
Location
Wakefield, UK
I'll be very interested in your experiences with the stiffer elastomers. It'll be interesting to see what, if any difference is made.

Regarding a trike feeling like a two wheeler:-
If you make a trike that feels exactly like a two wheeler then what advantage does that trike actually offer? Why suffer the weight of the trike for it to feel just like a two wheeler? Shouldn't it behave differently in at least one or more respects to make it worth the effort? I'm thinking here of primarily being able to hold it up at a stop without putting a foot down. If it behaves 100% like a two wheeler then the only "advantage" is the coolness factor of having a third wheel yet still tilt and whilst I've certainly employed that reason myself to justify my own designs I know that reason isn't enough for everyone.

The Mosquito 4 bar link movement is controlled, on the Mosquito, by the bars so removing that control mechanism to try to move it by weight shift and balance is going to be a tough ask Paul especially as it doesn't swing in a simple arc. I'm not saying such control is impossible, just that you'd be starting from a position of what I suspect is basic principles not being in your favour.
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
I'll be very interested in your experiences with the stiffer elastomers. It'll be interesting to see what, if any difference is made.
I want to see if it is less nervous and less likely to tilt when not wanted if I stiffen the tilt response , I cannot go much harder with M10 fastening only swapping out for 2 x 203 kg

Regarding a trike feeling like a two wheeler:-
If you make a trike that feels exactly like a two wheeler then what advantage does that trike actually offer? Why suffer the weight of the trike for it to feel just like a two wheeler? Shouldn't it behave differently in at least one or more respects to make it worth the effort? I'm thinking here of primarily being able to hold it up at a stop without putting a foot down. If it behaves 100% like a two wheeler then the only "advantage" is the coolness factor of having a third wheel yet still tilt and whilst I've certainly employed that reason myself to justify my own designs I know that reason isn't enough for everyone.
Usually you see this phrase from people who have built a :-
a) iLean trike no static stability
b) parallelogram style tilter again no static stability

usually they are built for racing so it is not a problem , almost no one is build a tilter to gain a higher seated trike like me ?

Unbelievably I have static stability , it stands on it's own does not fall over even when I sit on it !

HOW DID THAT HAPPEN ?

The Mosquito 4 bar link movement is controlled, on the Mosquito, by the bars so removing that control mechanism to try to move it by weight shift and balance is going to be a tough ask Paul especially as it doesn't swing in a simple arc. I'm not saying such control is impossible, just that you'd be starting from a position of what I suspect is basic principles not being in your favour.
Yes see post I made in your thread on a failed Mosquito , I have to many other things try to pursue a likely lemon at this stage...

Paul
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
The Finn's , leaders in Flevobike/trike developmant have suggested zero trail for both steering and tilt.

This is not possible with the steering for a Python front end like mine , however it may be possible for the tilt ?

They described it to me thus :-

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.


However the current setup was not designed for it and is getting very complicated under the tilt/front end pivot area ?



They have posted this :-



I need to measure the angle of the blue line and see if it falls into the envelope of a rod end bearing with a horizontal mounting ? maybe the top fixing just needs moving ?

Paul
 
Joined
Oct 19, 2012
Messages
1,505
Location
Wakefield, UK
I'll be the first to admit my knowledge on flevo systems is very limited. It looks like if the tilt axis doesn't intersect the front contact patch then tilt will change the python pivot angle. If the tilt axis hits the road ahead of the tyre then tilt will cause the front to drop increasing the python pivot angle. If the tilt angle does hit the front contact patch the python should then behave like a two wheeled python.
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
It looks like if the tilt axis doesn't intersect the front contact patch then tilt will change the python pivot angle. If the tilt axis hits the road ahead of the tyre then tilt will cause the front to drop increasing the python pivot angle.
As my tilt angle is infinite ? ie. parallel to the ground it does not contact the ground anywhere in my line of sight :whistle:

I had not considered it's effect on the Python pivot angle , however it does go someway towards explaining why even with a limited 25' - 30' front tilt [ by the steering damper ] there are times when leaning hard over I feel the pedals could touch the ground.
An anomaly I did not mention as it has not caused any concern and could prove useful :D

If the tilt angle does hit the front contact patch the python should then behave like a two wheeled python.
Don't say that ...I can't ride a 2 wheeled Python , infact I have one in the bike shed I was going to gift on here to anyone who wants to take it on !

As always grateful for any [ sensible ] input (y)

Paul
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
Popshot/Emeil/DannyC

Any speculation if I kept the 2 stiff dampers and rode it without the front rod end bearing at all ?

Paul
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
Yes

Just a though and not definite , it makes the tilt trail infinite as it is parallel to the ground.
However if it is not connected ........
Answers on a postcard please to the usual address ...

Paul
 
Joined
Oct 19, 2012
Messages
1,505
Location
Wakefield, UK
I suspect your elastomers would then be free to bend under less control making it like riding a jelly. Even pedalling could have them wobbling fore and aft. That rod end adds a lot of limitation as to where those elastomers can give.
 
Joined
Sep 16, 2018
Messages
1,077
Location
Netherlands
I think just as Popshot, that it will be more wobbly. It can then move in a directions.

I was thinking that maybe it is better to make a mount also in the front. Then it only tilts and will it not steer, because it rotates in the line of the trike.
Also will you make that ad the road is angled, you can tilt and still go straight.
But it is just a theory and I don't know if it solves any problem. I only then mount the handle bar to the steering part.
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
Ok getting a bit of tilter envy ?

Popshot is on his 3rd and I have only had a brief [ if unsuccessful foray into iLean ] so I had a better but undeveloped iLean rear end this would give me more width than first attempt and allow for elastomer damping ......
What can possibly go wrong ?



2 x BB and a short frame , I cut down some pedal cranks and fitted them to the inside tapers , I then cut some 1" tubing to join them together bit of flappy disc latter and they fit Hooray you say .

BUT

I had not welded the original parts accurately enough and so it would not turn.

Answer cut through the square cross tube and do some bending [ to the left of the B ] now it turns freely.

3 welds then one each end of the round tube and one 3 sides of the square tube , ' jobs a goodun '

The pedal cranks are that way around for welding to get the tapers inline then one will be reversed.

So the observant amongst you will notice I mentioned elastomer damping ? so where does that figure ?


One option is like this to bind it with old inner tubes ?

The other option would be to introduce one or more elastomer's between the centre of the joining tube and the square frame , if there is room ?

it is disassembla-ble which helps one of the BB's can come out from the side and the centre tube is then freed , this allows drilled and welding to the central tube/

Will it work ?

Well it will tilt real easy ! the whole trike will tilt unlike the current arrangement , so I may not be able to ride it although the added width and the damping should all help tame it...

Why am I trying it ?

Well in all honesty it is simpler than the current tilter and is easier to make it will just bolt to any Python spine , probably be made much lighter and can be made quite compact and has a suspension effect ?

Living on the wild side Paul
 
Joined
May 31, 2013
Messages
3,113
Location
South Benfleet, Essex, England, UK
Popshot/Emeil/DannyC

Any speculation if I kept the 2 stiff dampers and rode it without the front rod end bearing at all ?

Paul
I agree, there will be MORE free movement/play in the system.
 
Joined
May 31, 2013
Messages
3,113
Location
South Benfleet, Essex, England, UK
Ok getting a bit of tilter envy ?

Popshot is on his 3rd and I have only had a brief [ if unsuccessful foray into iLean ] so I had a better but undeveloped iLean rear end this would give me more width than first attempt and allow for elastomer damping ......
What can possibly go wrong ?



2 x BB and a short frame , I cut down some pedal cranks and fitted them to the inside tapers , I then cut some 1" tubing to join them together bit of flappy disc latter and they fit Hooray you say .

BUT

I had not welded the original parts accurately enough and so it would not turn.

Answer cut through the square cross tube and do some bending [ to the left of the B ] now it turns freely.

3 welds then one each end of the round tube and one 3 sides of the square tube , ' jobs a goodun '

The pedal cranks are that way around for welding to get the tapers inline then one will be reversed.

So the observant amongst you will notice I mentioned elastomer damping ? so where does that figure ?


One option is like this to bind it with old inner tubes ?

The other option would be to introduce one or more elastomer's between the centre of the joining tube and the square frame , if there is room ?

it is disassembla-ble which helps one of the BB's can come out from the side and the centre tube is then freed , this allows drilled and welding to the central tube/

Will it work ?

Well it will tilt real easy ! the whole trike will tilt unlike the current arrangement , so I may not be able to ride it although the added width and the damping should all help tame it...

Why am I trying it ?

Well in all honesty it is simpler than the current tilter and is easier to make it will just bolt to any Python spine , probably be made much lighter and can be made quite compact and has a suspension effect ?

Living on the wild side Paul
We need a "ride-report" don't we? :) Glad you got it done OK.
 
Joined
Oct 19, 2012
Messages
1,505
Location
Wakefield, UK
In all fairness Paul my first was an unmitigated failure and I've yet to finish the 3rd so I've only made 1.5 tilters.

I'm not sure you want any resistance on an ilean. The whole ethos of an ilean is it's completely free to tilt and rides exactly like a two wheeler, requiring balancing but with the advantage of having some suspension effect at the rear. The wider the ilean the greater the suspension effect but the less it will tilt. From some guesstimation of the width of that set-up you look to have somewhere around 26 degrees of tilt in it. I've assumed 175mm cranks and 700mm between the tyres centres. If I'm out, and that's likely, then you'll want to put your own figures into a triangle calculator to see your actual max lean. Width between tyres on one side - 2 x crank length on another with 90 degree angle between those sides.
It's quite arguable as to what minimum maximum lean you need but I'd open the bidding with 30 degrees. You can recover more lean by lengthening the cranks if you require a minimum width though the ones on your ilean look to be alloy.

 
Joined
Oct 19, 2012
Messages
1,505
Location
Wakefield, UK
An idea Paul.
What about using one medium elastomer in a direct line between the python pivot and the front wheel chassis? This would act as a steering damper but with a degree of self centring which a traditional damper does not provide. That may allow you to then place the bars on the non tilting part to keep upright at a stop.

Up to now your efforts have gone into finding a natural tilt because you want your hands to control the front. The ilean should be what you are looking for but if that doesn't work you could change that ethos about to try to make the python front feel natural allowing your hands to control the tilt. That way round would keep you upright at a stop and the elastomer on the python part may be a solution.
 
Joined
Sep 16, 2018
Messages
1,077
Location
Netherlands
Ok getting a bit of tilter envy ?

Popshot is on his 3rd and I have only had a brief [ if unsuccessful foray into iLean ] so I had a better but undeveloped iLean rear end this would give me more width than first attempt and allow for elastomer damping ......
What can possibly go wrong ?



2 x BB and a short frame , I cut down some pedal cranks and fitted them to the inside tapers , I then cut some 1" tubing to join them together bit of flappy disc latter and they fit Hooray you say .

BUT

I had not welded the original parts accurately enough and so it would not turn.

Answer cut through the square cross tube and do some bending [ to the left of the B ] now it turns freely.

3 welds then one each end of the round tube and one 3 sides of the square tube , ' jobs a goodun '

The pedal cranks are that way around for welding to get the tapers inline then one will be reversed.

So the observant amongst you will notice I mentioned elastomer damping ? so where does that figure ?


One option is like this to bind it with old inner tubes ?

The other option would be to introduce one or more elastomer's between the centre of the joining tube and the square frame , if there is room ?

it is disassembla-ble which helps one of the BB's can come out from the side and the centre tube is then freed , this allows drilled and welding to the central tube/

Will it work ?

Well it will tilt real easy ! the whole trike will tilt unlike the current arrangement , so I may not be able to ride it although the added width and the damping should all help tame it...

Why am I trying it ?

Well in all honesty it is simpler than the current tilter and is easier to make it will just bolt to any Python spine , probably be made much lighter and can be made quite compact and has a suspension effect ?

Living on the wild side Paul
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.
 
Joined
Feb 7, 2008
Messages
3,151
Location
Nottinghamshire England
In all fairness Paul my first was an unmitigated failure and I've yet to finish the 3rd so I've only made 1.5 tilters.
Soon I will have caught you up then :D

I'm not sure you want any resistance on an ilean. The whole ethos of an ilean is it's completely free to tilt and rides exactly like a two wheeler, requiring balancing but with the advantage of having some suspension effect at the rear. The wider the ilean the greater the suspension effect but the less it will tilt. From some guesstimation of the width of that set-up you look to have somewhere around 26 degrees of tilt in it.
Vi who developed iLean has made some claims that have not been verified by anyone else to the best of my knowledge [ I am not saying he is lying , just that there seems to be no other people trying the same stuff ]

So a Python with a iLean rear end made from a single BB is just a 2 wheeled Python - I cannot ride one and am to old [ and crusty ] to learn !
However a wide iLean can be self stable and stand on it's own , want to guess how wide ? no idea so have to try it for myself.

Vi states a iLean with elastomer damping can be used as a aid to learning to ride a Python , so maybe the 2 are a halfway house between unridable and needs a little seat time ?

The elastomer may help the suspension effect by damping the reaction to bumps as well as tilting ?

I've assumed 175mm cranks and 700mm between the tyres centres. If I'm out, and that's likely, then you'll want to put your own figures into a triangle calculator to see your actual max lean. Width between tyres on one side - 2 x crank length on another with 90 degree angle between those sides.
I have cranks between 140mm and 170mm to try , I will only try 180' as that is what the elastomer will be added for.
IIRC wheel track is around 25" but need to measure that , if it is then that will be narrow enough for me.

It's quite arguable as to what minimum maximum lean you need but I'd open the bidding with 30 degrees. You can recover more lean by lengthening the cranks if you require a minimum width though the ones on your ilean look to be alloy.
I reckon 30' is good , and I think running out of tilt at 30' will stop it tearing the elastomers apart ? unless of course that comes with 180' rotation of the inner axle joiner ?
Alloy ones were just added to get the tapers in line , the 140mm one's are already attached to the wheels ...
I think that increases tyre scrub , however that may only be for narrow iLean maybe the rules change as it gets wider ?
We have a welder any length is possible however I have gone for 140mm to keep it's overall length as short as possible

Paul
 
Top