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Witty custom user title
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I'm finishing up selecting components for a 1X gravel build, and have never really had to figure out gear ratios and and the like, so I need some assistance from those who know this stuff inside and out. So on my previous 2X build, my highest gear was a 36-28, which has always been plenty for me, even on the longer, steeper climbs. In looking at a gear ratio calculator, that works out to like a 1.3 gear ratio.

So if my highest gear on the 1X build is 42-32 (which appears to also be a 1.3 gear ratio), I should be working with basically the same thing for climbing? The reason I'm looking at this option, is I already have the 42t front crank/ring, and would just get an 11-32 cassette to match (and already have the long cage rear).

I'm a reading this correctly? Any help would be appreciated.
 

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Bianchi-Campagnolo
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Banned Sock Puppet
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You got it right. A ratio is a ratio, and 2 equal ratios are equal even if they are made with different numerator and denominator.

If you want to use the traditional terminology that bike guys are used to, calculate the "gear inches" rather than the ratio of ring and cog. That allows you to factor in different wheel sizes if you're comparing different bikes. Gear inches is kind of a historical holdover -- it's the diameter of a direct-drive wheel that would give the same rollout -- but it's immediately intelligible to people who've been doing this. Divide ring by cog (as you did to get your ratio), then multiply by the outer diameter of the wheel in inches (for the typical 700C25 tire that's about 26.5 inches). Your 36/28 and 42/32 are both about 34 inches.

One more terminology note: That's your lowest gear, not your highest. The highest gear on your new setup will be 42/11, or about 101 inches.
 

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Bianchi-Campagnolo
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Thanks, Lombard, but I think the Germans got it better, or?
 
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