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Velocipedia

gianlucagimini.it

21–30 of 110 posts

Re: Velocipedia

#22

bicycles facing left: 75 % bicycles facing right: 25 % That's unexpected. For some reason I'd think more would be facing right than left, and if I were to draw one it would probably be facing right too. I don't know why but it seems to feel more "natural". I just Googled images for "bicycle" and 32 out of the first 40 were facing right. I noticed all the renders were facing right as well, even if the original drawing…

Most traffic signs and signs on bicycle roads have bicycles facing left, maybe that's why?

https://rowerowapila.files.wordpress.com/2013/05/wp_000139.j...

Re: Velocipedia

#23

I couldn't draw a bike until I started fixing them. And I rode every day :/ Besides that, the renders are beautiful.

For me the most impressive thing is - these are not renders. (S)he had done it in photoshop.

Re: Velocipedia

#24

bicycles facing left: 75 % bicycles facing right: 25 % That's unexpected. For some reason I'd think more would be facing right than left, and if I were to draw one it would probably be facing right too. I don't know why but it seems to feel more "natural". I just Googled images for "bicycle" and 32 out of the first 40 were facing right. I noticed all the renders were facing right as well, even if the original drawing…

I would draw it facing left and I think that's because of the way I learned to mount a bike: the bike-stand is on the left side so you need to have your last foot on the ground on the left side in order to pull it up.

Re: Velocipedia

#25

bicycles facing left: 75 % bicycles facing right: 25 % That's unexpected. For some reason I'd think more would be facing right than left, and if I were to draw one it would probably be facing right too. I don't know why but it seems to feel more "natural". I just Googled images for "bicycle" and 32 out of the first 40 were facing right. I noticed all the renders were facing right as well, even if the original drawing…

I would draw it facing left and I think that's because of the way I learned to mount a bike: the bike-stand is on the left side so you need to have your last foot on the ground on the left side in order to pull it up.

Nice explanation! I'd also paint it that way and thought this was because bikes on advertisement materials are usually shown that way around.

Re: Velocipedia

#26
The first bike is missing its chain stays, the bars connecting the bottom bracket to the rear axle and the ends of the seat stays. Wikipedia has a nice diagram with the names of all the parts of a bicycle [1].

There are real bike designs that have a monofork (a one-sided fork, e.g. the Cannondale "lefty"), a monostay, or a solid body instead of top & down tubes (e.g. many folding bikes or the extremely aero Ventum One [2]). The Giant Halfway [3] folding bike has all three features!

[1] https://en.wikipedia.org/wiki/File:Bicycle_diagram-en.svg

[2] http://www.slowtwitch.com/Products/First_look_at_the_elusive...

[3] http://www.giant-bicycles.com/en-in/bikes/model/halfway/1905...

Re: Velocipedia

#27
post #13

Earlier quoted context omitted.

Just to expand on what others said, the tubes that the frame is missing are called chainstays.

Is it really impossible to build such a bike? Given a strong enough material it would be possible. I have not idea about the structural analysis in this case. Does such a material exist?

Likely not impossible, but the crucial weak point would probably be the connection with the seat tube. Independent of the material, that place would need some heavy gusseting/reinforcement. That particular bike also has a very vulnerable connection to the head tube, as only the down tube connects to it.

There are bikes without a rear triangle, but they (almost?) always lack the seatstay instead of the chainstay or have what could be considered something in between a chainstay/seatstay. Here are some examples:

http://i.imgur.com/F1xkdc1.jpg

http://i.imgur.com/oTFbEy7.jpg

http://i.imgur.com/XxRNe5y.jpg

Re: Velocipedia

#28
post #9

Earlier quoted context omitted.

But the front wheel is also missing that beam on a correct bicycle. Edit: implying: if the front wheel doesn't need it, why would the rear wheel?

I would like to see you turn a bike with front-wheel chainstays. Straight-only driving, turns are obsolete! :D Also, the front wheel is connected to the frame in a very different way than the back wheel: single strong tube, only diverging further on; and there is no requirement for the front wheel to be powered - therefore the front wheel can (and does) move WRT the frame, something the back wheel must not do. Yes, t…

You can actually turn by leaning in the correct direction. This is actually the usual way to turn if you're no-hand biking.

http://www.wikihow.com/Ride-No-Handed-on-a-Bike

Re: Velocipedia

#29
post #9
post #4

Earlier quoted context omitted.

No frame between rear wheel and front chainring. No strength.

But the front wheel is also missing that beam on a correct bicycle. Edit: implying: if the front wheel doesn't need it, why would the rear wheel?

Front wheel is attached to a thick tube that is almost vertical (weight tries to compress the tube), and that tube is attached to another thick tube throught a wide strong pivot that keeps the angle between the tubes constant.

Back wheel is attached to two thin rods at 45 degreee angle. Weight tries to push the seat down and push the back wheel away (to increase the angle). That's why we need another tube to hold the wheel at constant disntance (and to keep the angle fixed).

You could probably make it work by creating similar strong joint keeping the angle between seat tube and wheel rods constant for the back wheel, but why? Hm, maybe to make a bicycle with both wheels turning :)

Sorry for my English, never had to describe bicycles and probably all the techincal terms are wrong :)

Re: Velocipedia

#30

bicycles facing left: 75 % bicycles facing right: 25 % That's unexpected. For some reason I'd think more would be facing right than left, and if I were to draw one it would probably be facing right too. I don't know why but it seems to feel more "natural". I just Googled images for "bicycle" and 32 out of the first 40 were facing right. I noticed all the renders were facing right as well, even if the original drawing…

My guess is, it's to do with left-to-right reading/writing.
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