[python] Re: New Python - 20" or 26"?

Hello Jaime and all,

first go check your inseam length:

http://en.openbike.org/wiki/Inseam_Length

Then, applying the table made by Dirk:

http://en.openbike.org/wiki/Wheel_Sizes

you can decide wether 26" really could fit you.
Then go check the material you have available for building. 26" parts are widespread and therefore no problem to get. 20" parts need special gearing, especially concerning the chainwheel, to reach good speed.
26" wheels smoothen out bumpy roads. If you have a 20" rear wheel and lots of bad roads around, it should be suspended. 26" wheels are NOT more stable than 20" at fast downhill speeds. It is not yet proofed, but it might even be the other way round. Turning circle gets smaller with the wheelbase.
The derailler of a 20" front wheel is very close to the ground. No good for offroad riding. 

Cheers,
Jürgen.


On 21.05.2008 17:57, Jaime Cristovao wrote:

Hello all

I am new here, and first of all, I must appologise, my english is not
as good as it should be. I am from Portugal, and just met the
recumbent world a few months ago. There are just a few (dozens?) of
recumbents in Portugal, mostly for rent, I suppose. As far as I know
there are also a few homebuilders around the country, but the vast
majority of the people (99,99999%) just ride standard diamond frame
bykes, mostly BTT. At the very beginning I found myself searching for
kyaks and canoes, as I live 10 Kmts far from the sea. I found the
IHPVA site as beeing very helpful, and ended up building a strange
kind of a boat, a pacific proa I didn't sail yet (just paddled).
Meanwhile I found very strange (for me) bike (and trike) pictures,
like the ones I saw in Copenhagen a few years ago - and later in
Amsterdam. Wiered at the beginning, the recumbent concept is by
itself very attractive; I found very good ideas side by side with the
worst ones, and ended up building a tadpole trike after months of
reseach on every site I found about the subject. I decided to build
instead of buying because most of them are very expensive (a regular
AL DF bike is about 300â?¬ up), and Portugal isn't really in the
center of Europe. Well, I uploaded some pictures to my very incipient
blog (covadaonca.blogspot.com - It's only portuguese, but I intend to
"upgrade" to a bilingual version). It is not a professional artwork
as I did not even know how to use the welder before, but it is the
best I could get these days. Well, the most important thing: it is a
very fun ride. Very stable as it have one full meter between front
wheels and less than 10 cms of ground clearance... and weights about
22 K (115 with the rider - me).  Need to improve braking, top speed
so far is about 45 to 50 Kmts (maybe 40 to 45)... the first version
had a 26" rear wheel, I hd to change to a 20" because it was too
short to my legs. I finnished it the weekend before easter and so far
have some hundreds of kilometers on it. As I want something more
practical to day-by-day use, I decided to build a bike. As I want
something different, I decided it would be a recumbent one. After
some research, I found Python on fleettrikes, and despite the fact it
seems a "little" difficult to ride at the first attempts, I decided
to build one. After all, I want something different. One thing I did
not decided yet: what is the best, 20" or 26" front wheel? I think I
will need a "small" turning radius - about 5 mts... I prefer the 26"
one, as it will probably be faster and more stable and comfortable,
but I don't want to end up with something absolutely unpractical I
will never use. So, in your opinion, what will be my best option?

Thank you all

Jaime Alexandre



============================================================

This is the Python Mailinglist

http://www.freelists.org/list/python

Listmaster: Jürgen Mages jmages@xxxxxx
To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx 
with 'unsubscribe' in the subject field.

============================================================

Other related posts: