Rear derailleur: importance of the B-screw
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Rear derailleur: importance of the B-screw
Hi,
Adjusting a new derailleur, and wondering the importance of the B-screw...
How should I set it? have the upper jockey as close as possible to the bigger cog when on the granny in front without it being unsafe?
I read that ~6mm was a good number... is that correct?
My actual question is: how important and/or critical is that?
Will this affect my shifting speed/quality?
I tend to ride small cassettes (I mean with small large sprockets: 12-23 being my favorite) which means an optimal B-screw setting would lead to it being pretty extreme a setting...
Is it worth it? or should I leave a bit of an extra slack to allow switching to a little larger cassettes for when I am climbing (12-25 is my mountain cassette)?
Thanks!!
Adjusting a new derailleur, and wondering the importance of the B-screw...
How should I set it? have the upper jockey as close as possible to the bigger cog when on the granny in front without it being unsafe?
I read that ~6mm was a good number... is that correct?
My actual question is: how important and/or critical is that?
Will this affect my shifting speed/quality?
I tend to ride small cassettes (I mean with small large sprockets: 12-23 being my favorite) which means an optimal B-screw setting would lead to it being pretty extreme a setting...
Is it worth it? or should I leave a bit of an extra slack to allow switching to a little larger cassettes for when I am climbing (12-25 is my mountain cassette)?
Thanks!!
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How should I set it? have the upper jockey as close as possible to the bigger cog when on the granny in front without it being unsafe?
I read that ~6mm was a good number... is that correct?
I read that ~6mm was a good number... is that correct?
I tend to ride small cassettes (I mean with small large sprockets: 12-23 being my favorite) which means an optimal B-screw setting would lead to it being pretty extreme a setting...
Is it worth it? or should I leave a bit of an extra slack to allow switching to a little larger cassettes for when I am climbing (12-25 is my mountain cassette)?
Or you can adjust it for the 12-25. The change is small enough that it will not be that far from the 12-23 - unless you're OC about your shifting then do the former.
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I find I like it as close as possible without catching. Makes for precise shifting.
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Since the B screw is a no cost adjusting aspect of the gear system why doesn't the OP (or any one else) simply change it and then see what shifting performance changes happen. Then draw their own conclusions. Andy.
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Turn the crank very slowly and shift from the next to largest cog to the largest cog. As you shift, watch the chain between the top of the pulley and the bottom of the big cog. There needs to be enough room between the the top pulley and the teeth of the big cog for the chain to pass through as the shift is made. If there isn't you'll see and hear it as it forces its way between the two bumping the pulley, cage and RD .