Scientists don't really know what keeps a bike upright...

[Panter]

http://www.science20.com/news_articles/why_does_moving_bicycle_stay-78139

I found this quite interesting (probably just me though)
If you start googling "gyroscopic precession," things get even more cloudy!

 

[MontyVeda]

as far as i understand, gyroscopic whatever keeping us upright has long been disproved, and it's more likely us humans are just better at balancing when going above a certain speed. It also works when walking along a narrow thingy such as a beam, toppled tree trunk, ect... it's also easier to balance a fully laden wheelbarrow when going quicker rather than slower too. It's all us and not the wheels... i think.

 

[Noodley]

I thunked it was stablisers...

 

[MontyVeda]

[QUOTE 1854672, member: 76"]But Monty, if it was all about balance, how would that explain my almost complete inability to walk following a night out last year, but I cycled home no problem?

There must be a speed component I agree, but there must be science somewhere.
...[/quote]

the science is that of the physics of velocity, and the biology of your inner ear sending signals to your brain from which you make minor adjustments to the position of your upper body and toes/feet in order to not fall over... you wasn't walking fast enough!

 

[colly]

But a bicycle pushed and let to run down hill will carry on for quite some distance if it is pushed hard enough. Eventually it will over balance to one side or the other, which if someone were sitting on it they would correct by steering away from the direction of over balance.

I mean if you just had a bike in your hand and simply let go it would fall over right away. By pushing it and getting it rolling you delay the over balance.

Something is going on ! We should be told what it is.

 

[fatblokish]

here, try this
http://www.boreme.com/posting.php?id=14764

 

[Arch]

[QUOTE 1854905, member: 9609"]Has any bike ever been kept upright without a human on it ? if so, I think there is a clue there to how they work!

just found a monkey on uTube and i'm sure a dog has probably achieved it, but can't find any evidence. So may be just creatures that can successfully balance on two legs. It clearly has little to do with gyroscopes and an awful lot to do with the semi circular canals within the ear[/quote]

<pedant>

That's an ape, not a monkey....

</pedant>

 

[BigonaBianchi]

I find it depends where I park mine

 

[Panter]

They can carry on without a rider, lots of vids on youtube of motorbike riders falling off whilst doing stunts and the bike carrying on until it hits something

 

[ohnovino]

I thought it was something like ...

You start an unmanned bike rolling in a straight line. If the front wheel turns to the left, the momentum of the bike is now to the right of its centre of gravity, so the whole bike will start to lean to the right. That tilt makes the handlebars turn the front wheel back to the right, and the bike straightens up. As the bike loses speed it also loses momentum and can no longer self-correct.

But then I'm still picking bits of tarmac out of my thigh from a crash last week, so what do I know about balance!