Can gear ratios of belt and chain drives be compared?
03-30-16, 11:54 AM
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Can gear ratios of belt and chain drives be compared?
Since it's still a number of teeth:number of teeth, or such completely different systems you can't have any expectations based on such comparisons even if everything else possible was identical between two examples?
03-30-16, 12:19 PM
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You don't need to count teeth. If you know the circumferences in the front and rear, you can still come up with a ratio no matter what the units. Teeth is just an easy metric, and ratios are easier when you only have integers to fool with. (There are no 48.7 tooth chainrings.)
03-30-16, 12:28 PM
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You don't need to count teeth. If you know the circumferences in the front and rear, you can still come up with a ratio no matter what the units. Teeth is just an easy metric, and ratios are easier when you only have integers to fool with. (There are no 48.7 tooth chainrings.)
03-30-16, 12:56 PM
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It's the same, divide chainring (beltring?) teeth number by sprocket teeth number and you get the ratio.
03-30-16, 01:10 PM
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03-30-16, 01:35 PM
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Actually, there are. Maybe not that particular example, but fractional tooth count sprockets are commercially available.
It's done by carefully machining the sprocket so that the chain doesn't ride all the way down to the root of the cog tooth. Some BMX outfit makes them. And they aren't horrendously expensive either.
It's done by carefully machining the sprocket so that the chain doesn't ride all the way down to the root of the cog tooth. Some BMX outfit makes them. And they aren't horrendously expensive either.
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