Re: Bicycle physics question

On Thu, 20 Jun 2024 17:26:39 -0500, AMuzi <am@yellowjersey.org> wrote:

On 6/20/2024 4:48 PM, Tom Kunich wrote:

On Thu Jun 20 14:40:19 2024 Frank Krygowski  wrote:

On 6/20/2024 11:27 AM, AMuzi wrote:

On 6/20/2024 10:17 AM, Frank Krygowski wrote:

>
If a cyclist were to repeatedly stand tall on the pedals, then crouch
as low as possible, then stand back up, he would not experience
accelerations and decelerations each time he did that.
>
That case is easier to explain. The relevant vectors are perpendicular
to each other.
>

>
Speaking of different aspects, a full upright stand on a descent and
then folding into an aero position makes for a dramatic speed change.

>
Of course. But that's entirely explained by aerodynamics. It's not
related to changes in the rider's potential energy relative to the road
surface.
>
--
- Frank Krygowski
>

 
 
 
 
When you are riding a bike you are gaining and losing energy via the motion of the CG of the bike in the depth of the gravity field. You are also losing more energy in a turn from tire forces. Because the depth of the gravity field is so deep and the change of the CG change of the bike is so slight you can only talk about the gains and loses theoretically. The loses from the tire shape into and out of a turn are more significant. But under normal conditions those are so slight that only racers can detect them because of the speed required to make signficant scrubbing actions detectable.
 
With a motorcycle it is easier to detect because of the much larger speed differentials and the much wider tires with consequen5tial inccrease in scrubbing energy.

>
Gravity field?
Is that like a corn field or more of a force field?

Next, we should discuss what's most aerodynamic bike finish. Paint?
Chrome? Stainless? Carbon fiber?