Originally posted by vivify Is there a point where the stability decreases the faster you go? For example, is a bike moving at 100 km per hour more stable than a bike moving at 30? Is a bike moving at the speed of sound more stable than a bike moving 100 km per hour?
If a cyclist were able to get anywhere near the speed of sound then shockwaves would start to form which would make the bicycle unstable.
Originally posted by DeepThought If a cyclist were able to get anywhere near the speed of sound then shockwaves would start to form which would make the bicycle unstable.
'Speed wobble
Bikes can occasionally become unstable while descending. Known by motorcyclists as a 'tank slapper', a shimmy or speed wobble is an unnerving oscillation in which the frame and fork twist from side to side and the front wheel jerks the steering left and right. If it happens, your instinct is to grab the bars firmly and brake hard. Both of these things can make the speed wobble worse!
You may never suffer from a shimmying bike. But if you do, the following advice could prevent a crash. Stand up on the pedals and, if the frame has a top tube, grip it between your thighs. This damps down the vibration. You can then brake gradually to a stop.'
Originally posted by Ghost of a Duke 'Speed wobble
Bikes can occasionally become unstable while descending. Known by motorcyclists as a 'tank slapper', a shimmy or speed wobble is an unnerving oscillation in which the frame and fork twist from side to side and the front wheel jerks the steering left and right. If it happens, your instinct is to grab the bars firmly and brake hard. Bo ...[text shortened]... n brake gradually to a stop.'
That subject also has a Wikipedia page [1]. Which goes into more depth about why it happens. Unfortunately the reference containing to a downloadable paper on the subject has a broken link.
In the PDF, a bicycle was created with an extra counter rotating wheel to counter gyroscopic effects. It was still rideable. Although it did make the bicycle fall over faster if it was not being ridden.
Originally posted by DeepThought That subject also has a Wikipedia page [1]. Which goes into more depth about why it happens. Unfortunately the reference containing to a downloadable paper on the subject has a broken link.
[1] https://en.wikipedia.org/wiki/Speed_wobble
Have a memory of seeing a motor cyclist experiencing extreme shockwaves while going for some speed record or another (might have been Evel Knievel). Can't be much fun falling off at that speed.
Originally posted by Ghost of a Duke Why, when I was a kid and tried to ride a bicycle 'hands free,' would I always veer off to the left? (Same thing happened when I hit a golf ball or kick a football).
Which side do you dress?
This could be the source of your instability.
Try reading "The Eastern Art of Balance" by Wun Hung Lo
Originally posted by twhitehead If a bicycle is falling to one side, and you steer to that side, the momentum of the bicycle is now slightly in the opposite direction which rights the bicycle. So the secret to riding a bike is to steer towards the direction you are falling. The design of the steering column helps by causing the bicycle to automatically steer in the direction it is falling or stay directly straight when upright. (assuming the wheels are correctly aligned.)
Yes, steering is essential. No one can stay balanced if the wheels are in a rut (caught in tram tracks, for example). Rolling wheels however are not essential; this can be demonstrated by any track cyclist.
30 Mar '17 03:07
What keeps a bicycle upright?
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