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GRX810/RX800 derailleur with 12 to 14 1st cog?

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GRX810/RX800 derailleur with 12 to 14 1st cog?

Old 12-21-20, 01:10 PM
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Igor_M
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GRX810/RX800 derailleur with 12 to 14 1st cog?

Does anybody have experience using a cassette starting at 12, 13 or 14 teeth with either the GRX810 or Ultegra RX rear derailleur? For both models Shimano claims the "low min" and "low max" to be 11 teeth, but cannot help but wonder whether this is simply because they don't offer anything else, basically. I really don't want/need an 11T 1st cog and would much rather go with the slightly better spaced options offered by Miche.
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Old 12-21-20, 01:52 PM
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I've set up plenty of bikes w/ a 14t small cog for juniors and they always work fine so I'd think it shouldn't be a problem. ALL of the current Shimano rr derailleurs are like that, they say '11t small cog' but they all work with other sizes.
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Old 12-21-20, 01:58 PM
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It says "low minimum 11T", which to me means they don't want you using a 10T or 9T smallest cog, and yes, these are both available. It does not mean you can't use a larger smallest cog so, 12T or 13T smallest cogs are fine. And you are correct, cassettes starting with anything but an 11T cog are increasingly hard to find and I also don't need or like them.
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Old 12-21-20, 02:24 PM
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I currently use 12-27 & 13-25 9 speeds on RDER's that are supposedly 11-3? with no problem.
Just screw in the B screw enough to not get rub if needed. You probably won't need to.
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Old 12-21-20, 03:58 PM
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Originally Posted by HillRider
...And you are correct, cassettes starting with anything but an 11T cog are increasingly hard to find and I also don't need or like them.
I find this irritating as well.
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