Shimano 12 speed B screw question

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Shimano 12 speed B screw question
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flag Garradmiller
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Posted: Feb 1, 2022 at 19:37 Quote
Installing a 7100 slx derailleur with a 8100 10-51 cassette.

Shifted to 51t cog with b screw backed out and not making contact i still can't get the alignment line to reach the bottom of the teeth. Seems to shift fine on the stand but is there something i should do to get the jockey wheel a little higher?
flag Branmuffin
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Posted: Feb 1, 2022 at 19:44 Quote
Garradmiller wrote:
Installing a 7100 slx derailleur with a 8100 10-51 cassette.

Shifted to 51t cog with b screw backed out and not making contact i still can't get the alignment line to reach the bottom of the teeth. Seems to shift fine on the stand but is there something i should do to get the jockey wheel a little higher?

Picture would help, make sure the b screw stop is where it should be.

Step 2 from the manual

http://https://si.shimano.com/api/publish/storage/pdf/en/dm/MARD001/DM-MARD001-04-ENG.pdf
flag Garradmiller
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Posted: Feb 1, 2022 at 20:11 Quote
B screw stop is per the manual tight up against the ledge on the hanger.
flag singleandluvinit
Posted: Feb 2, 2022 at 19:50 Quote
The derailleur isn't compatible with the hanger, Shimano didn't seem to do a lot of testing with existing hangers to ensure compatibility. If its a Transition then they made a new hanger that will work with it.
flag trustywheels
Posted: Feb 2, 2022 at 22:50 Quote
Check chain length with suspension compressed. Likely chain is too short.
flag JonnyTheWeasel
Posted: Feb 2, 2022 at 23:53 Quote
My XT 12 speed actually needed a longer b-screw fitted to get correct alignment.

Photo?
flag Garradmiller
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Posted: Feb 3, 2022 at 7:36 Quote
Not a transition, this style hanger.
photo
[PI=https://store.khsbicycles.com/wp-content/uploads/2015/03/KHS-73-079-320a-rgb.jpg][/PI]The derailleur isn't compatible with the hanger, Shimano didn't seem to do a lot of testing with existing hangers to ensure compatibility. If its a Transition then they made a new hanger that will work with it.[/Quote]
flag Garradmiller
O+
Posted: Feb 3, 2022 at 7:39 Quote
trustywheels wrote:
Check chain length with suspension compressed. Likely chain is too short.

This could be possible will do.
flag Garradmiller
O+
Posted: Feb 3, 2022 at 7:40 Quote
JonnyTheWeasel wrote:
My XT 12 speed actually needed a longer b-screw fitted to get correct alignment.

Photo?

Think that would be the opposite, im using no b screw at all.

Will get an actual pic when i can
flag Branmuffin
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Posted: Feb 4, 2022 at 6:52 Quote
Did you check chain length yet? B screw and chain length are very important to getting the shifting right with the Shimano 12 speed, I assume this isn’t shifting great with the clutch engaged?
flag Garradmiller
O+
Posted: Feb 4, 2022 at 11:38 Quote
Branmuffin wrote:
Did you check chain length yet? B screw and chain length are very important to getting the shifting right with the Shimano 12 speed, I assume this isn’t shifting great with the clutch engaged?

Haven't yet need to break it open and check the length. Same chain was used before so i assumed it was right.

Doesn't shift bad with the clutch on or off
flag Branmuffin
O+
Posted: Feb 4, 2022 at 14:18 Quote
If you converted from 11sp to 12sp the chains will very likely be different lengths. The chains are also not compatible with each other.
flag Garradmiller
O+
Posted: Feb 4, 2022 at 15:14 Quote
Branmuffin wrote:
If you converted from 11sp to 12sp the chains will very likely be different lengths. The chains are also not compatible with each other.

came off a 12sp bike but will double check the chain part number
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