What would happen if I built a Mosquito / Python hybrid trike ?

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Hi all

This is a Mosquito trike , lean steer and the under pining's of the Mosquito Velomobile.


So if I built the rear end vertical and the Python pivot /front end did the steering , and handle bars attached to the steering part.

Would it be :-
a) normally un-tilted when ridden - due to the pendulum stability of C of G underneath pivot
b) tilt when cornering without needing to be made to ? i.e NO tilt controls
c) self righting after cornering ?

Could it have:-

  1. narrow track of around 22" to 26"
  2. seat height of around 14" to 18"
Answers on a postcard please to the usual address ....

Yes I appreciate the moving uprights need to cross for it to work better than the one pictured above.

Some thoughts on this may stop me wasting hours building a Python rear end to prove/disprove the theory ?

Paul
 
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Hard to say Paul. I need to ponder on that one. Getting the seat higher should not be an issue and a higher seat will help in not hitting the wheels with a narrow track. The way the swing happens on a Mosquito isn't the same as simply swinging with centripetal forces in a nice arc so I suspect it wouldn't swing much.
 
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Getting the seat higher should not be an issue and a higher seat will help in not hitting the wheels with a narrow track.
Shouldn't be a problem because it will be 40" wb.
The way the swing happens on a Mosquito isn't the same as simply swinging with centripetal forces in a nice arc so I suspect it wouldn't swing much.
But is that because the Mosquito has an angled forward blue vertical members adding a sort of rake into the steering pivot ?
Don't forget the Mosquito cannot steer without leaning , hence the controls needed to force the lean.

I am wondering if the blue bars were vertical and steering started with the normal Python steering front end/pivot then the tilt would be completely free to tilt when the turn started and tilt would be proportional to the radius of turn and the speed ? because of the Python steering front end/pivot the trike could be brought out of the turn using that and so the tilt would be removed ?

Maybe there would need to be some damping/stiction in the system to stop it over shooting before it rested in it's new position ?

What I am trying to achieve is a tilt that does not need controls of any kind for it to start and stop , hence any controls would ONLY be for steering.

I cannot get your idea of dual function bars to work in my head ?

Say you had only the left hand on the bars , although two bars AND two hands were available.
To turn right you would push the left bar forward with the left hand.

If the trike was traveling straight ahead but tilted towards the left to correct that you would have to push on the left bar , exactly the same as the right turn ?
So in your dual controls you would have to have your right hand also on the controls AND use exactly the same force pulling with the right hand as you used pushing with the left ?
I have already discovered that pushing on fixed bars is far easier to correct tilt that trying to pull on them.

regards Paul
 
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This is a Mosquito trike , lean steer and the under pining's of the Mosquito Velomobile.
This looks hideously complicated to me. All those cables, a drum and push/pull bars etc. and why is that cross brace bent in a "V" What function does that serve?
 
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You could
. and why is that cross brace bent in a "V" What function does that serve?
Purely an aesthetic choice by the builder.

I think the only type that will swing naturally is the type that has a fixed pivot line like this one



The centre of gravity would need to be lower than the pivot line so no high seat but it would swing just fine. The issue is the weight of the rider is acting on that top pivot to try to tip it over so no narrow track either.

I think the Mosquito wouldn't swing naturally because of the moving nature of the line of pivot which is all over the place due to the 4 bar link rather than any inbuilt lean.
 
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This looks hideously complicated to me. All those cables, a drum and push/pull bars etc.
But the whole point is to throw all that stuff away ? I ain't building a Mosquito !
Don't forget the Mosquito cannot steer without leaning , hence the controls needed to force the lean.
Paul
 
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I think the only type that will swing naturally is the type that has a fixed pivot line like this one



The centre of gravity would need to be lower than the pivot line so no high seat but it would swing just fine.
Surely if tilting is added the seat can be within my height needs as long as the pivot is above it ?
I assume I can make the pivot horizontal as I don't need the rake effect of that angle ? as I am not building lean steer ?
The issue is the weight of the rider is acting on that top pivot to try to tip it over so no narrow track either.
Will that change this drawing then ?




I am trying not to get fixated on high seat and narrow track , if the seat could be 15" to 19" I could live with a track say 28 " ?
I think the Mosquito wouldn't swing naturally because of the moving nature of the line of pivot which is all over the place due to the 4 bar link rather than any inbuilt lean.
The 4 bar just causes the rider to swing in to the inside of the turn so delaying roll over ?


Paul
 
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The pivot needs to intersect the front tyre contact patch or a lot of weird and very unwanted things will happen. Think of where that front contact patch will move to with a horizontal pivot - it'll move a long way sideways as you lean and that horizontal pivot will angle down towards the front. Quite large and horrible geometry changes. The higher the seat the higher the pivot needs to be to keep the centre of gravity below it and the more leverage the riders weight shifts will have on it in an attempt to pull it over, especially with a narrow track. I'd only want to use one of these with a low seat and wide track.
 
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A. The Mosquito is self leveling because of the c of g.
B. You need help to tilt. You probably can steer a bit by leaning, but assistance is best by the mosquito. On roads that are angled, you probably need to use that system also, to go straight.
C. I will self level after a corner.

  1. A narrow track is possible, but because you move your center of gravity to the outside of the trike, you will be able to tilt it over as it is to narrow.
  2. Putting the seat higher is possible, but there are limits and it depends on how you do it. Ad you take that Mosquito from the photo and you only move the seat up, you will loose some stability.
As you cross the uprights, then making it narrower is less of a problem.
But you still need assistance with steering.
You can ad an under frame, that helps as you move the seat up and with the tilting.


The other version can without assistance for steering. It can also be a bit narrower, justike the crossed design with the mosquito.
You can raise the seat and also raise the piviot.
The angle on the piviot makes how much you steer as you lean. The more horizontal, the less steering.
I have seen one one youtube and he added bars to the rear part so he could still help it steer.
That is handy as you go slow and need to make a small corner.

By both trikes, the pibiot angle decides what turning circle you have.

With the mosquito, you can even ad, tilting rear wheels. Mot easy to ad, but it is possible.
 
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The pivot needs to intersect the front tyre contact patch or a lot of weird and very unwanted things will happen. Think of where that front contact patch will move to with a horizontal pivot - it'll move a long way sideways as you lean and that horizontal pivot will angle down towards the front. Quite large and horrible geometry changes.
Something a normal Flevo trike does not have , the Finn's speculated that the Flevo trike would handle better with a ' Zero trail ' tilt pivot , however no one has built one yet ?
My current hybrid has infinite trail tilt.
It is possible I may build my new one like that , currently stalled due to domestic implosion .
The higher the seat the higher the pivot needs to be to keep the centre of gravity below it and the more leverage the riders weight shifts will have on it in an attempt to pull it over, especially with a narrow track. I'd only want to use one of these with a low seat and wide track.
Noted.

Paul
 
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A. The Mosquito is self leveling because of the c of g.
B. You need help to tilt. You probably can steer a bit by leaning, but assistance is best by the mosquito. On roads that are angled, you probably need to use that system also, to go straight.
C. I will self level after a corner.


SO A) and C) are good

I don't want to help it tilt I want to steer and have it tilt of it's own accord ?

But you still need assistance with steering.
Full Python steering as above , there will be a usual Python pivot between Python front ans middle frame , handle bars on steering part just not shown for clarity

So full steering available irrespective of tilt.

What I want is a design where the tilting is self righting and and it is self tilting when steered and does it all automatically.
Steering is done by the pilot.

Impossible , well maybe....

Paul
 
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Wait I need to explain b better. You steer by tilting, but to tilt, you need assistance.

The angle of the rear makes how big your turning circle is, just as the other one.

As you want to ride it without hands and steer without hands, than is the mosquito not the best to have.



First one is just a beautiful build, but not for in the city.
Second one has a smaller turning circle.

I think that you want to do this on your trike.
 
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I think the only type that will swing naturally is the type that has a fixed pivot line like this one

Now that is far simpler and easier to make. However, as a tilt-steerer it appears to lacks the "Python-Pivot" so presumably it can only steer when tilted?
I wonder what happens when/if you mix the free swinging pendulum tilt like that with a Python-Pivot? Interesting.
 
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Wait I need to explain b better. You steer by tilting, but to tilt, you need assistance.

The angle of the rear makes how big your turning circle is, just as the other one.

As you want to ride it without hands and steer without hands, than is the mosquito not the best to have.
Not quite I want to tilt without hands , and steer with hands.
I have much fear steering with feet !


First one is just a beautiful build, but not for in the city.
Yes Mosquito is an open road machine and poor [ compared to my Python ] turning circle

Second one has a smaller turning circle.
I suspect unstable at speed and poor grip climbing ?

I think that you want to do this on your trike.
Nah it's the wrong way around !

Thanks for your input Paul
 
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Now that is far simpler and easier to make. However, as a tilt-steerer it appears to lacks the "Python-Pivot" so presumably it can only steer when tilted?
Yes lean steer , like aluminium the work of the devil !

I wonder what happens when/if you mix the free swinging pendulum tilt like that with a Python-Pivot? Interesting.
... and so do I !

Paul
 
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Not quite I want to tilt without hands , and steer with hands.
I have much fear steering with feet !
OK the mosquito will stay up but tilting and steering is linked.

Yes Mosquito is an open road machine and poor [ compared to my Python ] turning circle
Depending the angle of the rear. You can give it a small turning circle, but you get those strange looking things.


I suspect unstable at speed and poor grip climbing ?
It is low speed and compared to the other mosquito, it is more a city trike, but not for touring.

Nah it's the wrong way around !

Thanks for your input Paul
The video was as example. It is a system like the other trike, but turned around and added tilting front wheels.
 
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