Gear ratios
09-30-2010, 01:12 AM
#1
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Gear ratios
Well......
I made a discovery today.
[&:]
I always thought that to calculate the gear ratio of 4 sprockets, you divide the large number with the small in each pair, and then add them together.
But it turns out that's not correct.
Divide both and then multiply them.
I made a discovery today.
[&:]
I always thought that to calculate the gear ratio of 4 sprockets, you divide the large number with the small in each pair, and then add them together.
But it turns out that's not correct.
Divide both and then multiply them.
09-30-2010, 08:35 AM
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RE: Gear ratios
so
35, 25 =1.4
25, 25 = 1
1.4*1=1.4thats not right....
35, 25 =1.4
25, 25 = 1
1.4*1=1.4thats not right....
[link=http://www.dynamicscience.com.au/tester/solutions/hydraulicus/gears1compound.htm]CLICK[/link]
This is why I'm posting this here.
The topic of gear reduction has come up a number of times here on the forum, and I was always under the impression that you divided and then added the two sums, and to be honest I can't recall anyone ever saying it was wrong.
I discovered it today when rotating a setup identical to the one in my picture, and realised that it wasn't 6.8:1 as I thought but 9.4:1.
Took me a while to get my head around it but then it all made sense.
The reduction between the first pair of sprockets is multiplied by the reduction between the second pair.
10-01-2010, 05:48 PM
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RE: Gear ratios
Your all making something so simple sound so complicating
Divide, divide and multiply.
What's so complicated about that?
[&:]
10-01-2010, 08:01 PM
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RE: Gear ratios
Notta... I'm referring to... Should I multiply/divide etc
You know me DVP... I guess i just assume one should have learned this in school...
No drama
Stoney
You know me DVP... I guess i just assume one should have learned this in school...
No drama
Stoney
