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Old 07-12-06, 07:18 PM   #1
smellygary
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Gear/inch formula

I can't seem to remember the formula to determine gear inches. Can somebody remind me? Thanks.
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Old 07-12-06, 08:19 PM   #2
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you'll need a slide rule. it's crank teeth divided by cog teeth, multiplied times wheel diameter.

it's easier to go here:

http://www.sheldonbrown.com/gears
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Old 07-12-06, 09:07 PM   #3
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crank teeth divided by cog teeth multiplied times wheel diameter.
52/11x27=127.64 gear inches
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Old 07-12-06, 10:11 PM   #4
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Quote:
Originally Posted by Moose
crank teeth divided by cog teeth multiplied times wheel diameter.
52/11x27=127.64 gear inches
Cool, thanks!
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Old 07-15-06, 11:37 AM   #5
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I refer to Sheldon's site a lot for gear inches and everything else bicycling. My LBS mechanic pointed me out to this site a few weeks ago, a pretty slick interface, a lil more info too...

http://www.jbarrm.com/cycal/cycal.html
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Old 07-15-06, 12:38 PM   #6
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However, if you want true gear inches, you'd better use the actual wheel diameter. A 700C wheel with narrow tyres is typically 26" in diameter. My 26" wheels with narrow slicks are a mere 24.5".
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Old 07-15-06, 03:14 PM   #7
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I believe you asked this exact question a few days ago and it led to an absurdly long thread for something so simple. Next time try the search function.
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Old 07-16-06, 07:36 AM   #8
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Quote:
Originally Posted by HillRider
I believe you asked this exact question a few days ago and it led to an absurdly long thread for something so simple. Next time try the search function.
Don't be an arse. Here is the thread your refering to:

Gear/inch formula

Check the dates of the OP. On the Board it did show smelly as the thread starter but somehow Retro's reply started a new thread with the same title. It was a glitch.

You are very salty.
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Old 07-16-06, 07:38 AM   #9
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Quote:
Originally Posted by Moose
Don't be an arse.
Check the dates of the OP. On the Board it did show smelly as the thread starter but somehow Retro's reply started a new thread with the same title. It was a glitch.
Not trying to be. The forum does get the exact same question from the exact same OP on occasion and this appeared to be one of those times.
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Old 07-16-06, 08:10 AM   #10
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I'm sorry. I didn't mean to itch my glitch in public!
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Old 07-16-06, 08:19 AM   #11
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As for the gear/inch topic being beat into submission in the imposter thread, I am with HillRider. Don't get too caught up in the numbers, just ride.
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