[python] Re: pictures again // small vs big weels
- From: Tihamer Juhasz <balamber@xxxxxxxxx>
- To: python@xxxxxxxxxxxxx
- Date: Wed, 22 May 2013 14:21:09 +0300
Hi Gerald,
Thank you for the reply and the information.
I spent some more time with my Python and this is what it turned into:
http://myrecumbent.blogspot.ro/2013/05/python-turned-peregrine.html
Regards, Tiha
On Tue, May 21, 2013 at 1:58 PM, Gerald <bepb@xxxxxx> wrote:
> **
> Hi Tiha,
> my congratulations to you new python, nice work.
>
> I ride both, a python with 405 (20") wheels and one with 622 (28") wheels.
> Both ride nice but also quite differently.
> Beside the obvious better maneuverability due to the shorter wheelbase,
> the 20" wheel passes more or less under by legs while cornering. This makes
> it even more easy to take tight corners.
> With my 28" Python, the front wheel is actually between my legs, and
> together with the seat, this limits the maneuverability significantly. But
> for speed on flat, open roads, the 28" python is the fastest (human
> powered) bike I have ridden yet.
> When you pick a big wheel, you should consider the required in seam length
> of you legs!
> Check http://en.openbike.org/wiki/Wheel_Sizes.
> Actually, for a first python you made a clever choice :-).
>
> As for moving the pivot behind the seat - one point certainly is if the
> seat is mounted to the rear or the front part. If the seat is mounted to
> the front part, the overall steering will change dramatically because you
> can't steer with you legs anymore. Don't know if you could consider it a
> python at all.
>
>
> Best regards
> Gerald
>
>
>
>
>
>
>
> On 13.5.13 17:56 , Tihamer Juhasz wrote:
>
> Thanks Philip. I made up a drawing for the front section, the wheel
> cage, in a 3D design sw to calculate the distances and the bend angles.
> Otherwise there was no precise plan before starting to build it. Just made
> some calculations on paper and did the rest of design on the fly while
> building it. The basic idea to run everything horizontal as much as
> possible was made prior to drawing or fabrication. Just two wheels and a
> straight line inbetween. Turned out really simple indeed.
>
> Tiha
>
>
> On Mon, May 13, 2013 at 5:14 PM, Philip Hahn <everphilski@xxxxxxxxx>wrote:
>
>> Tiha,
>>
>> I love how clean your bike looks. Did you make up drawing prior to
>> fabrication or did you go by trial and error?
>>
>> Beautiful Python!
>>
>> philip
>>
>>
>> On Mon, May 13, 2013 at 6:42 AM, Tihamer Juhasz <balamber@xxxxxxxxx>wrote:
>>
>>> Hi all,
>>>
>>> Made some more decent pictures and shared them in a Picasa album again:
>>>
>>> https://plus.google.com/photos/115292543199069523585/albums/5877419428757741505?authkey=CK7Kp9yb07HK4QE
>>>
>>> I hope the pictures explain how the pivot works. It actually works
>>> well, but it seems not strong enough to last long. Will see.
>>>
>>> I presently ride the bike like an agitated orchestra conductor, waving
>>> around randomly with my arms, but its a lot of fun. Its really refreshing
>>> to learn something this basic at this age. I make steady progress each time
>>> I take out the bike, so its reassuring too. Any tips on riding are welcome.
>>> I did not mount a handlebar yet, so I learn hands free.
>>>
>>> A few questions: how much does the trail and wheel size influence the
>>> riding behaviour of the bike? Are bigger wheels better for riding
>>> stability? Has anybody tried to have the pivot behind the seat? I would
>>> imagine that pedal induced steering would be even less if the pivot was
>>> right behind the seat support point, so almost at the center of gravity and
>>> behind the rider hip joints. And one more: how about having a reversed
>>> python? That is, move the pivot back to the hind wheel and have it mirrored
>>> (at 115 degr (180-65) or having it at 65 degr. This would be a rear steered
>>> bike I know, but there are a few which work.
>>>
>>> Thanks,
>>> Tiha
>>>
>>
>>
>
>
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