Geometry Argument

by Andy Shen

Section head text.

Schmalz still on vacation, so I propose a geekfest argument.

The geometry of a bike is truly miraculous: a bike will tip over if you let it go, but it requires almost no conscious effort to keep upright when riding. It’s so stable you can steer it with nothing but your hips. It has two big built in gyroscopes to keep it tracking, and it’ll turn automatically to catch you should you lean one way or the other. It’s also the most efficient form of transportation: the energy from a ham sandwich will get you very far. Just ask Toto.

So here’s the question. If bikes never existed, would you be able to invent it? How many generations would it take to get it to today’s refined state? Would it even occur to you to create a vehicle on just two wheels?

39 Comments

Steve Hampsten

Chariots had two wheels, no? Weren’t they invented by Charleton Heston before he became fixated on guns? We could just ask him to invent a bike for us – problem solved.

Anonymous

One of the Organic Athletes guys in the 123 race at Maltese was racing on a bamboo frame from Calfee! I wonder if it had hemp lugs and was tofu powered!

Anonymous

I think that’s a typo. Should read whiners jersey’s in honor of all the great nyvelocity commentary.

Anonymous

if other Tom is Dolan, you already know this since we talked about it the other night…just posting for the benefit of anyone who might have a semicompact with a tall head tube who a) might not want to drop the cash on another frame and b) not have looked around much for shorter headsets and -17 stems (which aren’t all that commonly available, it turns out)

mike berk

It is a little bit of a problem if you ride a somewhat bigger bike (57 and up) Replace the headset top cap (FSA makes a 10mm), then get a -17 degree Ritchey 4-Axis stem. Problem solved, 11.5 cm saddle-to-bar drop achieved, albeit for another $75-100 bucks. That said, geometry-wise I’d have to say the bike seems nice and stable, and handles really well. Works fine for racing I think; if only occasionally for placing (but that’s really my own damned fault, and not the bike’s.)

Anonymous

I remember in the 80s, I was explained sloping top tubes were for girls(women)…now even Trek is giving in now that Lance is gone?…More sloping tubes or? Is the mast-like part-o-the-frame seat post here to stay? Integrated headsets putting Chris King out of business? Will Shimano go internal cable? I wonder if UCI will change the weight limit now that bike tech has improved so much more. Water bottles on down/seat tube more aero than the behind-the-saddle-tri holder?

jp

i looked at the website for dynamic bikes.
looks great for commuters but still heavy and slightly less efficient than a perfectly tuned chain system. there is a similar thing with motos…almost all high performance/racing bikes still use a chain.

byx

the bike emerged from possibility when the fruits of industrialization freed man enough to build bike chains for an alternate type of individual transportation

the other tom

my orbea geometry is very “low rider” or “hybrid” or even… shall i say, “gay.”

it’s perfect for a low seat to high handlebar ratio which has become so popular among the heavy belly, hairy leg recreational crowd. They don’t have to stack 5 spacers above the headset!

note to all serious racers – avoid silly orbea geometry.

jft

I think I’d conceive of scooters similar to the one’s people are using now. Whether that’d lead to pedal bikes I don’t know. But the term “push bike” I think came from early scooters with seats that involved into real bikes.

Also, if you ever are in North Carolina, check out the Wright Bros museum

Orcutt

Someone comes out with a shaft drive every decade (it started around 1900) and it doesn’t get the job done.

Anonymous

“I think it was one of Newton’s laws/theories”

Newton was a chump. Einstein’s theory of relativity (on one end) and Quantum Physics (on the other) throw Newton’s theories into disarray.

But to answer Andy’s question, even the roundness of a wheel would never have occurred to me.

Potty

seems to be the thing that keeps the bicycle upright. I can’t remember all of it (20 something years ago and I did not really pay attention) but I think it was one of Newton’s laws/theories where you would need a force in a different direction to stop or change the momentum of any moving object as in when a taxi, dog, or other obstacle comes into your path. To stand on one skate or roller blade is pretty hard but when you move forward, your forward momentum is what keeps you up. I think, but am uncertain about it, that the gyroscopic effect and power generated by it could aid in taking us down when we touch wheels or when you change direction too quickly. Maybe Andy can do an experiment. He and Dan when he’s back. In the park after a race. We should get a high definition video camera and film exactly what happens when they tough wheels and when the guy at the back goes down. I know that Andy has brittle bones so maybe it could be Dan at the back.

Andy

I guess that makes sense. You’re no less stable when you switch to superlight wheels, but a change in fork rake is detectable.

Ray Alba

Actually – There is a bike that came out a few years ago that was shaft drive – which I thought WTH – Supposedly the developer was going to make shaft drive racing bikes – bet they couldn’t get the weight down –

Here is a company I just found.
http://www.dynamicbicycles.com/

Anonymous

Amazing to me how the current rear-wheel chain drive design has not changed in what, over 100 years? Yeah, tweaks here and there, and of course materials but, the design is basically unchanged.

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