Danny's Daily Delta

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Do you use the handlebar to steer?
As I am totally new to any form of Python, the answer is yes! I am using a mix of both leg & arm.
Uphill and pedaling seems reasonably OK. It is when coasting and especially downhill it goes all over the place and keeps trying to climb the camber and cross over the road. :eek:

Don't compere your experience with Paul because his python is not a python, its a train.
Why do you say Paul's is a train? In what way is it a train, I don't understand?
 
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May I ask "What angle is your pivot at?"
Just over 57 deg.

Python riding is a handsfree experience, I went to a off road track and it took 4/5 days of practice before I made the first handsfree lap.
Today I ride 95% handsfree. You don't get full controll of a python before you can ride it handsfree.
Mine gets very lively when you go past 20mph, it's when I can't keep a steady pressure on the pedals it gets wobbly.
So downhill is no pedaling, a stabilising hold on the handlebars and a few prayers.
 
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Just over 57 deg.

Python riding is a handsfree experience, I went to a off road track and it took 4/5 days of practice before I made the first handsfree lap.
Today I ride 95% handsfree. You don't get full controll of a python before you can ride it handsfree.
Mine gets very lively when you go past 20mph, it's when I can't keep a steady pressure on the pedals it gets wobbly.
So downhill is no pedaling, a stabilising hold on the handlebars and a few prayers.
Thanks for this info Pegasus.
A call was placed to the Python-Gods on my behalf and the concensus from mount Olympus was that my C-of-G is in the wrong place which is magnifying my problem a lot.
Some "modifications" may have to be made. But first I am going to make it so I can alter things easily to arrive at a "train" like setting so it feels like it is on rails.
Sadly, I have no "off-road" track to practice on which is why the tendency for it to bolt for the other side of the road is so alarming. :eek:
I do want this to be a success after such a lot of effort on my part and extensive help and advice from others, so I shall persevere.
 
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I think with camber that it's not so much the front wanting to turn up as the pivot wanting to get to the lowest point possible (same effect I know but it's not just pedantry on my part). The front pointing up is a symptom, whereas the pivot going down is the cause. A python self centres by the riders weight forcing the pivot to it's lowest setting. On a flat road the lowest setting for the pivot leaves the front wheel straight ahead. Road camber moves the lowest setting towards the curb thus pointing the front up and I can't see an engineering solution to remove that. You could lessen the effect by moving your weight further back thus placing less weight on the pivot. It should (in theory) reduce the desire of the pivot to head for the gutter but will also reduce the self centring effect. A steering damper may help in moderating the effect too but there's a good chance that it's a matter of learning the techniques necessary to overcome the physics. Not being a pythoneer I have no idea what those techniques are.
 
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Yes indeed Popshot & Pegasus. Both points are understood.
Its a bit of a conflict in parameters that requires balance I guess.
"Get your weight over the pivot and a decent pivot angle for maximum self-centring". Vs. "Climbing the camber at every opportunity".
The degree of the violence/force in the climb up the camber is really alarming for a novice pythoneer.

So this morning I created some fish-plates from 4mm plate steel to allow me to split the main frame at the suspension pivot and clamp the two halves side-by-side at varying lengths to discover the best length for a revised Centre-of-gravity.
Here's some pictures of the plates and 10mm bolts and a foreshortened frame. Wheelbase is currently 37" (down from 49") so that may very well move the COG.



 
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Not being a pythoneer I have no idea what those techniques are.
If you try with your mind to controll the python, you fail. You have to let you and the bike become one with no mind interfering.
I used to look to the left of the front to turn left, if I tried to turn to the left conciously I struggled.
Now I just ride.
 
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I think it's fair to say you've lost the dead axle suspension at that level of pruning without some reworking. I'll look forward to a report on the difference (if any).
I think that's true. :ROFLMAO:
It never really was there for the suspension per-se, it was there in order to fold the trike in half as the rear half could fold completely under the rest of the frame.
But yes, I think any hope of suspension is a vain one.
 
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Update 26th April 2020:

The delta-snake has been seriously "bobbed" I measured it when I had the 2 halves overlapped and the wheelbase was likely to be 37".
However, it was NOT possible to actually make it that short AND keep the pivot in the frame so I had to compromise and dock the frame severely while keeping the pivot in place.
All the work is completed, I have ridden it, and it isn't as "lively" as before and it is livable with. Everything from the main frame's pivot forwards is unchanged.

This is how short it was with the plates on for the first test ride note the mounting point for the suspension link in relation to the rear-beam/axle



But back in the real-world.....this is how much I was able to trim off and still retain the pivot/fold. So it is 3 or 4 inches longer than the minimum length I test-rode it at first before making any changes.



The end result is walked round in the clip below.


There is more trouble ahead...
On the last test ride I detected a flexing/movement at the pivot to front-triangle/frame when pedaling ( a slight rocking/bobbing). I may have to improve that connection as it is oscillating on 2 M8 bolts. LOL.
 
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Nice

So which of the 2 pairs of M8 bolts does it rock on ? vertical or horizontal ?

Do you think these also had same problem ?





They make your 49" look short !
 
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So which of the 2 pairs of M8 bolts does it rock on ? vertical or horizontal ?
It is these 2 here.... look closely.
The whole front tri-mangle is bolted through crush-tubes inside the 38 x 19 box into a 25 x 25mm square tube with a 3mm plate inside the front face with M8 nuts welded on the rear-face of that.
If I push down on the BB shell at the front, I can feel a movement at the meeting point of these two box sections. The 38 x 19 is rocking on the 25 x 25.
UPDATE:
My initial thoughts are to put 2 uprights off the pivot to sit directly behind the 2 uprights from the front triangle and put 2 more bolts higher up to stop it "rocking" on the one 25mm section.


 
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Dan

So the error was made here :-



The cross piece you cut a huge hole in to weld around your pivot outer shell should have been welded vertically instead of horizontally ?

Not sure why you chose to weld captive nuts inside tubing etc however that now severely limits your choices ?

Looks as though there is just room for a piece of tubing above that for another bolt ?

 
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The cross piece you cut a huge hole in to weld around your pivot outer shell should have been welded vertically instead of horizontally ?

Not sure why you chose to weld captive nuts inside tubing etc however that now severely limits your choices ?

Looks as though there is just room for a piece of tubing above that for another bolt ?
Indeed Paul. Some poor choices were made in that regard. However the intention to go horizontal at the time was to avoid the risk of tube distortion whereby the bearings would no longer fit.
Captive nuts were purely aesthetics. So I shall look for ways to stabilise the mount with additional attachment. The choices are limited, as you say.
 
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Update 29th April 2020:

Today was a wet and windy day but an opportunity presented itself to push the tadpole out into the damp and pull the delta apart to do some more work on that.

I did not get too much accomplished but every tiny step forwards is a bonus. Today I managed to mount a front mudguard. It is a tight fit but the tyre does not rub anywhere and it seems to be a good rigid mounting.
The mudguard is on backwards (I don't think it knows or cares) and what is now the front end will be bolted to a sturdy wire bridge that is fixed on M6 bolts through the frame and the dropouts.


The rear end (that had a convenient mounting bracket riveted to it) is tethered by a small section of 12 x 3 mm bar threaded for an M5 bolt. This may leave enough of the mudguard exposed to have the actual mud-flap fixed onto it.



Then I removed all the cables and the handlebars and started to measure and cut the steel tube for the additional supports for the pivot to prevent the "rocking" of the front frame on the pivot mount.

And then it started raining properly and I was forced to come indoors. If it brightens-up I may venture back out again.

EDIT @ 17:39PM
Well it did stop raining (a little) and I ventured outside to try and place additional attachment points support on the pivot.
It was a horrible job, I am not in the least delighted with it, but it is done.

From the front.


And from the rear.

NOT the prettiest job, but as it is performing a "belt & braces" function, I don't care. It can be as ugly as it likes. So there! :ROFLMAO:
I am losing the will to live with this trike. 🤪

 
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Dan

Looking good , no need for the mud flap to be fastened to the mudguard [ that is so old school :ROFLMAO: ]

Just add a couple of brackets under the two lower bolts in this picture set back about 10mm from the inner edge



This will give more clearance for the tyre and mean you can take either off without disturbing the other
 
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Update 30th April 2020:
The only thing that got done today was the disassembly of the entire front triangle and it getting a wash in "panel-wipe" and the first coat of paint. I think 2 coats will be required to hide all the screw-ups properly protect the surface from the elements. For any of you that are curious about the colour it is indeed bright yellow.
Apparently its the law, ALL Pythons are to be coloured in HAZMAT/DANGER colours to alert the unsuspecting public. If the hairy stick can survive its dunking in the Hammerite then another coat can go on tomorrow, else I shall be looking for another sacrificial hairy stick. IMHO it doesn't look too bad in this colour. Any motorist that declares "Sorry, I didn't see you there" may need to have their eyesight checked.

 
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I see sums yellow and sums not ?

Got a bit of rain as well ?

Never found anything to clean Hammerite off brushes and so use those ' use once ' ones , once the first 30 bristles have fallen out I find they are good to go...
 
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I see sums yellow and sums not ?

Got a bit of rain as well ?

Never found anything to clean Hammerite off brushes and so use those ' use once ' ones , once the first 30 bristles have fallen out I find they are good to go...
Bits that are NOT yellow, will be BLACK, weather has been a little bit challenging. The hairy stick in use ATM is indeed a disposable 10 for a quid "Silverline Special".
I am being encouraged to put some "banding" on the paintwork by our "artist in residence" (SWMBO) and this may indeed happen.
If I put 20 bright lights on the front of the trike I can call it a "Vespa" and take it to Brighton perhaps? ;)
 
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