Paul´s flevoproject

[Vilijami]

All steering and tilting geometry is hard to explain and understand even in finnish languague. All people here not signature my opinion. But i try share my experience and theory what making sense in my mind. Whole geometry is so complicated, so i tell you very simplex version. Of course speed influence centrifugal force.

Infinite tilt trail? Do you mean, than tilt axle is horizontal? Ball on the hill. In slow speed cyclist mass try fall tilt down and additionally fast corner centrifugal force fights against tilt angle.

Tilt pivot height? I think lower is better, but trail is -in my opinion- so much important. Low tilt pivot and high seat is problem, wich i not yet inventor really good solution.

Paul, thank’s when you ”force” me to practice my English

[paul_n]

Hi there

Yes current tilt axis is horizontal as Eric's Flevotrike.

I suspect your assumptions are based on behaviour you witness whist riding those not inconsiderable km

I to am doing that as best I can to figure out what is happening , or asking when the answer to me is not obvious , km probably about 78 however climbing slowly

I have noticed gratuitous tilting being employed ?

I now tilt in places where on my non tilting trike I would have not expected to need/use tilt !

Hope my English [ which is not the best , despite it being the only language I speak/write ] is not causing you to much confusion.

Paul

[paul_n]

Ok got problems with my prototype ?

Pythons suffer from instability at speed a weave that cannot easily be controlled when all steering is done by leg, it if cannot be caught early the oscillations become bigger and can result in a crash.[ rider-induced oscillation. ]

I was free wheeling at probably 24mph with a car behind when I got into a fast oscillating swerve , the legs are quite an imprecise steering method and it is very difficult to make small corrections.
I did think briefly I was a goner and would either swerve into the stone face on my left or into the oncoming traffic , thankfully the oscillations damped and I was able to recover it , a lucky escape.

Maybe a wake up call I really need to put more effort into finding a steering solution I am happy with and can use ?
I looked through my Flevobike/trike pictures and 18 different one's 13 had bars on the steering part and only 5 on the non-steering part [ one had both ] a hint I think (y)

So I decided to try and ride my trike using handlebars on the steering part and only short fixed bars under the seat for starting and low speed manouvers this did not go well !

Manged to ride it off my drive using the fixed bars , move hands to other steering bars struggling to keep it moving vertically and straight ahead , never made the first 90' right turn , lack of steering locked forced me onto someone's drive which I had to back off and ride on the pavement to get back on road.

Wobbled around a car till I reached a turning circle on my right , usually set tilter up for a sweeping 90' right and 360' left [ very Red Arrows ] , never made it around the right ! it tilted that much [ no feeling of controlling tilt at all ] almost fell out of seat whilst I scrabbled to unclip right foot and get it planted on the ground.

So back onto drive very gingerly and tried a track stand something I could do quite easily with non-steering bars , couple seconds then a wobble tilting to right began again , almost fell out of seat whilst I scrabbled to unclip right foot and get it planted.

That ride is +/- 250 yds/mtrs !

So I can ride the tilter with no bars on the steering 72 miles [ 115 Km ] with only 1 really serious incident , and now I can't ride it 250 yds

This is further than I recall every getting with bars on the steering when trying before causing me to settle on bars on the non-tilting part.

What I don't understand is WHY ?

It would be simple to assume :-
a) years of riding Python trike made hands free come relatively easy ? [ had to so go on with it ]
b) I am actually trying to ride this like a Flevo BIKE which is something I cannot ride ? - so maybe I got a long way for a non Flevo rider ?

What next ?

Any ideas what is happening

regards Paul

[hjv1527]

My experience with flevo and steering is as follows: I started with trike and I found it much easier to have the steering attached to the rear part. I think I kept the whole trike upright with hands. The rear was "steady" with the extra wheel and I was able to force the front to stay upright with muscles.

Since my goal was to change the rear as bike rear, I started to practice to ride hands free. In two wheeled mode it would not have been possible to use the rear as support. I also tried several different steering bars to get the position of hands to feel natural.

After getting used to not-so-stiff upper body and cycling experience, I changed the steering to front. The starting, first kick on the pedal, was the most difficult after change. By counter steering a bit with hands, it became doable. On ride I just tried to rest my hands on the handle bars and let the legs do the steering. The key seems to be to keep the legs as relaxed as possible.

Very soon after that I changed the bike rear and started riding two feeled. I find it even easier to ride than to ride a trike.

[paul_n]

Harri

Does a Flevo bike/trike suffer from high speed stability issues as I have described ?

The Python's problems with this issue are very noticeable when you are not pedaling.

Even without the large frightening oscillation's it has a weave from side to side when free wheeling at speed.

Paul

[hjv1527]

No, I haven't felt that. My problems only start if I get scared and/or stiff at legs.

Viljami (if I remember right) told that there are two sizes of flevo bikes. The smaller one has more stability issues due to different trail. I seem to have the bigger frame and it is a bit clumsy at low speeds and in crowded areas, but does not have problems at speeds. I have ridden about 50 km/h downhill without problems. (Both not pedaling and pedaling)

[jooseha]

Harri

Does a Flevo bike/trike suffer from high speed stability issues as I have described ?

The Python's problems with this issue are very noticeable when you are not pedaling.

Even without the large frightening oscillation's it has a weave from side to side when free wheeling at speed.

Paul

I think that Python has wrong geometry.
I have more upright steering axle and smaller trail than average python. About 67° and -15cm. It´s higher also. I don´t have any high speed stability issue. It´s very relaxing rolling downhill. Maybe steeper and longer hill could take easiness away, but I couldn't find big enough yet

[paul_n]

Well there's a turn up for the books ?

Look what I have just bought ?

Do I refurbish my original Flevobike trike and see if I can ride it ?

As can be seen behind my prototype I also have a shabby fibreglass back box for it...

Which fits in this hole.

it has
438 x 20 rims [ listed as Dutch juvenile ] don't expect tyres or tubes being available in this size
old school wood valve inner tubes
rim dynamo
Magura hydraulic rim brake
Front hub 3 x 6 with hub brake
front ring 62T
box
lights
stand
more elastomer's than you can shake a stick at
2 handle bar positions

It came in 4 parts so I have no idea what does and doesn't work , nor whether I can ride it.
Someone reversed it with the cables loose and the front cassette has attempted to eat the rear derailleur cable so that will probably need changing.

Fun , fun , fun .....

Paul

[paul_n]

Hi all

Well time has passed and tilting seat Pythons are now at Tilt#6 , however it works very well.

It is narrow track = 60cm
High seat = 40cm
Wheel base = 104cm

It stands without a tilt lock and is easy to ride , it is lively when travelling straight over uneven ground , however does not feal dangerous or out of control.

I have done the following tilting Kilometres

Tilt#2 = 115 Km - retired - dangerous
Tilt#3 = 437 Km - [semi] retired - proved tilting seat concept
Tilt#4 = 217 Km - [ semi ] retired - will be born again Tilt#6 ?
Tilt#5 = 131 Km - [semi] retired - still usable [ at present ] should Tilt#6 need work
Tilt#6 = 50 Km
Total = 950 tilting Kms so far..

All the best Paul

[Härski]

Kertokaa mulle.

Miks täytyy saada penkki notkumaan polkuvoimien mukana? . Tämän lisäksihän keskipakovoima kallistaa kuskin ulkokurviin ja heittää pois kyydistä. Ellei siis väkisin väännä itseään keskipakovoimaa vastaan.

Mä en oo ilmeisesti ihan sisäistäny näiden laitteiden ideaa!

Sori en jaksa leikkiä tulkkia, kun nykyään saa tekstit halutesssaan käännettyä niin helposti.

[jori]

Kertokaa mulle.

Miks täytyy saada penkki notkumaan polkuvoimien mukana? . Tämän lisäksihän keskipakovoima kallistaa kuskin ulkokurviin ja heittää pois kyydistä. Ellei siis väkisin väännä itseään keskipakovoimaa vastaan.

Mä en oo ilmeisesti ihan sisäistäny näiden laitteiden ideaa!

Sori en jaksa leikkiä tulkkia, kun nykyään saa tekstit halutesssaan käännettyä niin helposti.

Ketjun alussa selviää, että syy kallistumismahdollisuuden tavoitteluun on pyrkimys kapeampaan raideväliin.