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

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So first assembly where I can sit on it .......



Oh sh*t look at the angle of the front end .almost 90' !

As Popshot predicted the tilting has increased the turning ability of the front end.



Around the back these 2 tubes should be parallel whoever you can see the top one is displaced to the right , it turns out this is only 7' of lean ? I was puzzled for a while as to why so little ?



That small amount of tilt seems to lift the front end up somewhat , not sure if that is desirable or not ?

So I took the dog for a walk and after ringing Southern accomplice with euphoric tales of hours from a test ride , realised what was happening the tilt/lean was hampered by the pedal crank hitting the ground !!!

Plonker , if I just sat on it with the front end vertical facing forwards then I could experience the full lean potential ?

So that's when it started to go wrong .....

Currently it has no pedals , needed for controlling the front tilt

and

Currently no rear brakes which are needed to stop it rolling forward.

With my hands on the rear wheels I explored the tilt , WOW can it tilt a long way and would seem to stay up right just with a wheel braked so it cannot roll ???

However when getting off ...

........ there was a sort of soft movement , in an unexpected direction , not sort of sprung'springing just like something giving .........



The 6mm pivot plate is bent big time !

without a wheel turning ......

Not unexpected but disappointing never the less

Hoping it can be cold bent back into position , it will need to be fairly accurate as obviously it needs bracing over the bend in some way.

Paul
Ahhhh...... with the front end attached only below the axis of the top tube I am afraid that was very likely to happen, although I did think 6mm plate would have been a bit "stiffer" than that.
Did you get "The 12 Pounds of Xmas" too? ;)
As you say, bend it back and put some side plates on and it will be as stiff as teenage morning wood. Job done.
Looking almost good. :)
 
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Ahhhh...... with the front end attached only below the axis of the top tube I am afraid that was very likely to happen, although I did think 6mm plate would have been a bit "stiffer" than that.


This is how it ought to be , however look how much higher the pivot needs to be ?

As you say, bend it back and put some side plates on
Dilemma front face or rear face ?

Front would seem to be better as they can then go way past the bend ?

On the rear they run the risk of interfering with the horizontal rod end pivot and attaching the pivot rod ends ?

Looking almost good. :)
Is that a split infinitive ?
 
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Nothing a large fine tuning hammer won't sort.

The back of the front end lifting under leaning is a result from the tilting pivots position relative to the python pivot in the vertical plane. The lower the python pivot is mounted on that plate the more that pivot will rise on tilting. If you mount it as in the above picture then the back of the front end will lower on tilting thus raising the BB. In real use you'll almost never have much turn on the front as it'll now lean cutting actual turning down to very little. Of course the lean itself will push one crank arm closer the pavement. You may need to raise the BB.

It still looks to me like the bars need to be on the fixed rear part allowing you to control the lean with the hands.
 
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In real use you'll almost never have much turn on the front as it'll now lean cutting actual turning down to very little.
yes that picture is the extreme , even my legs can't fold like that.

It does show that it does not collapse in a heap like a laundry drier rack :-



Oh and DannyC's tilting trike :whistle::whistle::whistle::whistle:😁


Of course the lean itself will push one crank arm closer the pavement. You may need to raise the BB.
Please go and wash your mouth out , more than once !

It still looks to me like the bars need to be on the fixed rear part allowing you to control the lean with the hands.
Now where's the fun in that ?

Tilt and steering involve 2 different motions ?
Tilt is push up down
and steering is push forwards and back ?

Well they do in my head .....

Paul
 
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ok having welding difficulties for some reason ?

I made the pivot mount from some acquired 6mm steel it had a gold finish looking more like anodising but grittier , I ground it back to shiny and have had a devils own job welding it.
Very porous welds and when welding there is a blue/purple haze on the edges of the arc area ?



as you can see the good the bad and the acceptable [ left to right ]

inside is worse



I will address the blobs and may clean up the inside to attempt to fill in the gaps between these welds but won't grind the porous one's out

All the welding done in short stretches to minimise distortion , then joined up on the outside etc etc



So this is what we are after ....

Bend now you bu**er !!!!!!

Paul
 
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You may need to raise the BB.
I think my front needs to be like this :-



and not like this



the upward rise between the front and rear tubes just in front of the axle will allow the rear tubes to be horizontal and the pivot be much easier to implement this will give a seat height similar to the 11" the new trike has ?

Paul
 
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Ok so cleaned up and bit more welding and now been reassembled.

No brakes but pedals added , so gripped rear wheels to stop it falling over and tried a tilt ......

Scary !!!! it just tilts and keeps on tilting , I could have fallen out 😨😨😨

Got off and when I had stopped crying I took the tiltometer to the seat , it was quite capable of staying leaned over @ 20' and would have gone further if pushed lightly !

So it can stand almost upright on it's own , but does no like the pilot :(

I am considering adding the second elastomer I have .



Like this.

It will:-
Stop the suspension - not a good thing

It will add resistance to the tilt , hopefully making it easier to ride for a novice.
As it can be bolted in and out it can be easily removed later if I get the hang of riding it ?

quaking in my boots Paul
 
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Ok so cleaned up and bit more welding and now been reassembled.

No brakes but pedals added , so gripped rear wheels to stop it falling over and tried a tilt ......

Scary !!!! it just tilts and keeps on tilting , I could have fallen out 😨😨😨

Got off and when I had stopped crying I took the tiltometer to the seat , it was quite capable of staying leaned over @ 20' and would have gone further if pushed lightly !

So it can stand almost upright on it's own , but does no like the pilot :(

I am considering adding the second elastomer I have .



Like this.

It will:-
Stop the suspension - not a good thing

It will add resistance to the tilt , hopefully making it easier to ride for a novice.
As it can be bolted in and out it can be easily removed later if I get the hang of riding it ?

quaking in my boots Paul
Paul,
Does our man in the states have the same experience I wonder? His elastomer is miles away from the rod-end IIRC?

It may also be why people often opt to have their bars on the rear half as it means they can automatically apply the steadying force as required.

Anyway, you have what you always wanted. A tilting trike. ;)
 
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Without the bars on the rear you will have to permanently balance it including at stops. Depending on how much, if at all, the wheelbase alters as it tilts then brake application may assist in stopping it falling over at rest. The less the wheelbase alters the less effect applying the brakes will have to that. I'd suggest that you want to be able to lean at least 30 degrees. It would seem that two elastomers may not let you do that.
 
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DannyC ' Anyway, you have what you always wanted. A tilting trike. '

Yes and I think if you had posted that lily-livered rant #589 I think I would have told you to stop whining like a girl and MAN UP !

PopShot ' I'd suggest that you want to be able to lean at least 30 degrees. '
It can tilt way more than that however persuading the rear end to tilt and holding the front end to stop it jackknifing and hold the angle'o'meter in the seat to stop it falling on the floor is beyond my meager 2 arms.
Unlike some people on BROL I have no objection to putting a foot down at a halt.

Pegasus - nice to hear from you , the idea is to get the seat higher which is why tilting is being explored - did you see I have copied your rod end bearing set up , looks good so far.

The test in #589 was not really carried out in idea conditions ?
The pedals had no clips so feet only resting on them
Hands had to hold rear wheels to stop them turning so I could not have my hands on the bars , which currently have no brakes.


My Python can now do this !

Now you can see why I run out of hands !

Tomorrow try to find time to cable the brakes up , then rear changer ...
Paul
 
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Paul,
Does our man in the states have the same experience I wonder? His elastomer is miles away from the rod-end IIRC?
Sadly not valid , he could ride a Python 2 wheeler before he built his hybrid.

It may also be why people often opt to have their bars on the rear half as it means they can automatically apply the steadying force as required.
We may yet prove the validity in that observation ?

Paul
 
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They ad also a dempener on the frond to limit the steering. With the tilt, the little steering is enough to make a corner.
 
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They ad also a dempener on the frond to limit the steering. With the tilt, the little steering is enough to make a corner.
Only because they chose a steering angle with no self centring when being ridden , so it has even less with no one on it !

Paul
 
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Ok it has been ridden very briefly.

snagging list :-
brakes cables drag on floor when corning/tilting
brake levers need raising on bar extensions
gear lever not tight enough so changing up as ridden
tops of bar extensions [ open ] need stoppers as trying to use them with mu thumbs on top to control the tilt is painful

so the ride ?
very brown trousers with above problems , tilt hard to control and like a very novice bike rider tending to slow down when in trouble only adding to the tilt instability I think.
On the way back I realised I could hold the rear dead axle with both hands , the tilt was immediately NOT TO scary however then there were no brakes available.

So conclusions ?
Two choices either.
a) Learn to ride with the bars on the front - possible ?
b) Add bars to no tilting portion and trust my feet will always be in control of the steering.

The coward in me wants option a) however if I tried option b) it may lead to me being able to ride a 2 wheeled Python ?

Paul
 
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Ok it has been ridden very briefly.

snagging list :-
brakes cables drag on floor when corning/tilting
brake levers need raising on bar extensions
gear lever not tight enough so changing up as ridden
tops of bar extensions [ open ] need stoppers as trying to use them with mu thumbs on top to control the tilt is painful

so the ride ?
very brown trousers with above problems , tilt hard to control and like a very novice bike rider tending to slow down when in trouble only adding to the tilt instability I think.
On the way back I realised I could hold the rear dead axle with both hands , the tilt was immediately NOT TO scary however then there were no brakes available.

So conclusions ?
Two choices either.
a) Learn to ride with the bars on the front - possible ?
b) Add bars to no tilting portion and trust my feet will always be in control of the steering.

The coward in me wants option a) however if I tried option b) it may lead to me being able to ride a 2 wheeled Python ?

Paul
Wow!
Congratulations on getting it ridden Paul. Well done that man! :D
Despite the "brown-trousered" moments, was the general "Straight-line" ride any different? Was the suspension effect evident?
On gentle cornering did it just want to keep tipping over?
Were the turns tighter?

I do think that a secondary set of bars off the fixed non-tilting section might be the answer or part of an answer.

As it is only the "mule" you do get the opportunity to try a few things out before committing to any specific solution. So the mule proves its worth. :)

It is a shame none of us can be there to film you struggling & falling off enjoying the new riding experience. :p
 
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Wow!
Congratulations on getting it ridden Paul. Well done that man! :D
Thanks

Despite the "brown-trousered" moments, was the general "Straight-line" ride any different?
Sadly yes ! It leaned and I had insufficient authority to get it vertical

Was the suspension effect evident?
No idea smooth road and fighting for control do not allow time for noticing ANY finer points !

On gentle cornering did it just want to keep tipping over?
As above

Were the turns tighter?
To slow to judge ?

I do think that a secondary set of bars off the fixed non-tilting section might be the answer or part of an answer.
Secondary ?

As it is only the "mule" you do get the opportunity to try a few things out before committing to any specific solution. So the mule proves its worth. :)

It is a shame none of us can be there to film you struggling & falling off enjoying the new riding experience. :p
Yes and good job !

Thank you for taking an interest .... now close the door please ....Paul
 
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Ok so current bars on front not working to well ?

Tried some on non tilting part :-



transferred the forward/sloping extensions over as they have the controls on them.



makes the front look clean ....



Only one derailleur connected and stops not adjusted correctly so cannot get all low gears however there is enough to stop the chain scratching the frame and to pedal it easily.



it is getting mightily crowded under t'seat !

You can see the tyres are wet , the rain made test flights unpleasant and stopped a comparison picture next to current Python.

How did it ride ? well no better still fighting for control and dreading it getting into a tilt especially whilst going straight and level as it where.

So dog walk and chewing the cud with DannyC I think I know what is happening and more to the point why , which equals solution possible ?

Bear with me whilst I try an explanation ...

if you sit on a dining chair with a wooden bar under the seat/buttocks and 90' to the bum crack with your arms vertical you can easily push yourself up off the chair ?
If you put the bar underneath your knees instead your elbows would be bent @ 90' and I cannot apply enough force to get my bum off the chair !

So the bar extensions that slope forward seem to be the main problem currently, with the horizontal bars in there current position I think I can reach them and there is room for the brake levers to be moved to them with hopefully a small vertical extension off the end for the gear changer ?

Musings and other thoughts solutions welcome of course.

Paul
 
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