Author Topic: Some interesting figures  (Read 2462 times)

phopwood

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Some interesting figures
« on: April 14, 2014, 07:05:53 pm »
I cycled 25.8 miles today and uploaded my data to garmin connect.  It gives some figure which got me thinking.

It told me my cranks had rotated 8388 times so I took this to the next step.  The 25.8 miles is 41521075mm and my wheels are 2023mm in diameter this means the wheels turned 20,524 times.

At this point I felt a bit sorry for those little ball bearings, just going around in cycles.

Peter

Andre Jute

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Re: Some interesting figures
« Reply #1 on: April 14, 2014, 07:23:08 pm »
At this point I felt a bit sorry for those little ball bearings, just going around in cycles.

You are truly a caring, sharing, compassionate man, Peter.

geocycle

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Re: Some interesting figures
« Reply #2 on: April 14, 2014, 07:38:43 pm »
Which reminded me of the two men in a ball bearing factory.  One of them lost his bearings, the other one lost his temper....
 

Danneaux

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Re: Some interesting figures
« Reply #3 on: April 14, 2014, 07:39:54 pm »
 ;D ;D ;D to all the above...!

All the best,

Dan. (...who suddenly feels joyful for the reading)

jags

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Re: Some interesting figures
« Reply #4 on: April 14, 2014, 08:29:35 pm »
this must be the comedians thread ;D

geocycle

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Re: Some interesting figures
« Reply #5 on: April 14, 2014, 08:33:18 pm »
Back to the OP I wonder how many times each ball bearing rotates. One for Jim perhaps?
 

rualexander

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Re: Some interesting figures
« Reply #6 on: April 14, 2014, 08:39:17 pm »
I cycled 25.8 miles today and uploaded my data to garmin connect.  It gives some figure which got me thinking.

It told me my cranks had rotated 8388 times so I took this to the next step.  The 25.8 miles is 41521075mm and my wheels are 2023mm in diameter this means the wheels turned 20,524 times.

At this point I felt a bit sorry for those little ball bearings, just going around in cycles.

Peter

2023mm diameter wheels? Is this a penny farthing?

(think you meant circumference?!)

phopwood

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Re: Some interesting figures
« Reply #7 on: April 14, 2014, 09:30:23 pm »
Quote
2023mm diameter wheels? Is this a penny farthing?

(think you meant circumference?!)

Yes good point, very valid and we'll delivered.  ;D

Quote
this must be the comedians thread Grin

Yes it is but I am worried it may turn in to a circular conversation

bikerta

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Re: Some interesting figures
« Reply #8 on: April 14, 2014, 09:42:40 pm »
[quote
Yes it is but I am worried it may turn in to a circular conversation

[/quote]


This is turning into a 'wheelie' funny thread     :D

JimK

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Re: Some interesting figures
« Reply #9 on: April 15, 2014, 12:08:26 am »
I wonder how many times each ball bearing rotates.

I think the ball bearing revolves around the axle half as many times as the wheel goes around. Then multiply that times (axle diameter / ball bearing diameter) to get the number of times the ball bearing rotates around its own axis.

Andybg

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Re: Some interesting figures
« Reply #10 on: April 15, 2014, 07:41:39 am »
I think the calculation would be:

Rb=((V/pyeDw)*pyeDa)/pyeDb

Where:

Rb =rpm bearing
V - velocity of the bike
Dw = Diameter of the wheel
Da = effective Diameter of the axle (diameter of contact between bearing and axle)
Db = diameter of bearing

If my 3rd year maths is still somewhere in there - lol

Andy

Andybg

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Re: Some interesting figures
« Reply #11 on: April 15, 2014, 07:52:19 am »
where pye is actualy Pi or 3.14159265 and if anyone can remember pi to more decimal places from memory they must be sadder than I