gear ratios...
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Hi to all,
sorry if this question might seem banal to you people, but I just realised (about time I did ??) that newer bikes have got much smaller chainrings than my 10 year old MTB... want to make sure before I buy some bits...
Is the gear ratio measured as the difference between the number of teeth between the chain ring and cog ? Would a, for example 44-11 gear ratio feel exactly the same as a 48-15 ??
thanks for any feedback
claude
sorry if this question might seem banal to you people, but I just realised (about time I did ??) that newer bikes have got much smaller chainrings than my 10 year old MTB... want to make sure before I buy some bits...
Is the gear ratio measured as the difference between the number of teeth between the chain ring and cog ? Would a, for example 44-11 gear ratio feel exactly the same as a 48-15 ??
thanks for any feedback
claude
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Chainrings
The formula is:
number of teeth on chainring/number of teeth on cog x wheel diameter = gear inches. The result is the distance travelled for one pedal revolution.
Hence 44:11 = 104 gear inches.
48:15 = 83 gear inches.
52:13 would give you 104.
A good cycle mechanics book should give give you a table of gear inch equivalents.
number of teeth on chainring/number of teeth on cog x wheel diameter = gear inches. The result is the distance travelled for one pedal revolution.
Hence 44:11 = 104 gear inches.
48:15 = 83 gear inches.
52:13 would give you 104.
A good cycle mechanics book should give give you a table of gear inch equivalents.
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so, if I understood correctly, my older bike with a 48:13 ratio would actually be slower than a newer bike with 44:11 ratio, although the difference in teeth is actually more in the older bike....
claude
claude
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You could always play around with the gear inches calculator on this page. https://sheldonbrown.com/gear-calc.html
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Unlikely for a "casual" cyclist. It would require an extreme degree of fitness to do so at those speeds due to wind resistance. For somebody my age, it would be torture feeling my knees grinding away slowly.
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You could always play around with the gear inches calculator on this page. https://sheldonbrown.com/gear-calc.html
epic thread dredge.
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You could always play around with the gear inches calculator on this page. https://sheldonbrown.com/gear-calc.html
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You could always play around with the gear inches calculator on this page. https://sheldonbrown.com/gear-calc.html
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Well as long as someone already woke the corpse -
That's the right formula but the wrong definition. The result is the equivalent diameter of a wheel that would travel the same distance in one revolution (like a penny farthing's wheel).
In other words, the distance travelled per pedal revolution is the (gear inches) * π.
In other words, the distance travelled per pedal revolution is the (gear inches) * π.
Last edited by DiabloScott; 05-07-24 at 06:02 AM.
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Hi to all,
sorry if this question might seem banal to you people, but I just realised (about time I did ??) that newer bikes have got much smaller chainrings than my 10 year old MTB... want to make sure before I buy some bits...
Is the gear ratio measured as the difference between the number of teeth between the chain ring and cog ? Would a, for example 44-11 gear ratio feel exactly the same as a 48-15 ??
thanks for any feedback
claude
sorry if this question might seem banal to you people, but I just realised (about time I did ??) that newer bikes have got much smaller chainrings than my 10 year old MTB... want to make sure before I buy some bits...
Is the gear ratio measured as the difference between the number of teeth between the chain ring and cog ? Would a, for example 44-11 gear ratio feel exactly the same as a 48-15 ??
thanks for any feedback
claude
Last edited by Camilo; 05-06-24 at 09:17 PM.