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Chainrings v cassette

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Old 11-26-16, 01:00 PM
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nightshade18
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Chainrings v cassette

Hi,

How does a tooth on the front compare to a tooth on the back?

I swapped my 28t cassette for a 30t, but now I'm thinking of changing my 36t chainring out for a 34.
Will 2 teeth less on the front give an equal reduction in gearing to my experience of adding 2 teeth to the cassette?

Thanks
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Old 11-26-16, 01:30 PM
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There are Different toothing Profiles for Both... But The Pitch standard is 1/2"

Can you do simple Maths ? Tooth count rear its turned by tooth count front in a proportion known as a Ratio..
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Old 11-26-16, 01:41 PM
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Think in terms of percentage change. The percentage effect is the same front or back except in opposite directions.

So adding 2 teeth to 28 is 1/14th or roughly 7%. subtracting 2 from 36 is 1/18th or a roughly 5.5%%. So the effect of changing the ring is slightly less than what you got changing the cassette
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Old 11-26-16, 01:43 PM
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I don't understand what you're trying to say.

My question was: is the reduction of 36:28 to 36:30 equal to the reduction of 36:30 to 34:30. Yes, I can do simple maths. No, I don't understand if the reduction is equal.
Sorry if I'm not up to standard
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Old 11-26-16, 01:45 PM
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Originally Posted by FBinNY View Post
Think in terms of percentage change. The percentage effect is the same front or back except in opposite directions.

So adding 2 teeth to 28 is 1/14th or roughly 7%. subtracting 2 from 36 is 1/18th or a roughly 5.5%%. So the effect of changing the ring is slightly less than what you got changing the cassette
Thanks - that was the kind of thing I was looking for
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Old 11-26-16, 02:07 PM
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Or, if you'd like the internet to do the maths for you, just use this gear calculator!

HTML5 Gear Calculator
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Old 11-26-16, 02:32 PM
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'Sheldon Gears' works well, too... Sheldon Brown's Bicycle Gear Calculator
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