Rear Derailleur Catch 22

Robert Lee said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

make sure shifter cable is smooth. Lube cable below bottom bracket.
make sure it has no kinks, bends, rust or anything that may interfere
with it. Maybe even replace cable.

Andres

Robert Lee said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

Sounds like inner wire/housing/under BB guide issues. Replace the
crappy 4mm housing with good 5mm, new inner wire, clean the BB guide
and...bob's yer uncle.

In article <[email hidden]>,

Robert Lee said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

I had this problem once with a touring bike and a Shimano XT 8-speed
derailleur. I think the flexibility of the chain was the critical issue.
I could find a setting for proper shifting in both directions only when
using a Shimano chain. It didn't work with a Sram/Sedis chain. Even with
the Shimano chain, the adjustment had to be right within half a turn of
the adjuster screw. Some years later I tried Sram chains again and they
now worked. Perhaps a new chain (less flexible?) would help in your case?

"Ned Mantei" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

In article <[email hidden]>,

Robert Lee said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

I had this problem once with a touring bike and a Shimano XT 8-speed
derailleur. I think the flexibility of the chain was the critical issue.
I could find a setting for proper shifting in both directions only when
using a Shimano chain. It didn't work with a Sram/Sedis chain. Even with
the Shimano chain, the adjustment had to be right within half a turn of
the adjuster screw. Some years later I tried Sram chains again and they
now worked. Perhaps a new chain (less flexible?) would help in your case?

Or a sloppy upper derailleur pulley, but I doubt that since the bike is only
8 months old. My bet is on a dirty, sticky cable. Do you use by any chance a
Nokon cableset? I experienced that same behaviour with that set. They use a
too soft liner, causing a small amount of hysteresus in the system.

Lou

Robert Lee said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

Probably the cable as Qui si parla said, but I wonder if this could also
be caused by the cassette lockring being loose.

Quoted message said:

My rear derailleur doesn't shift cleanly. If I increase the cable
tension, the derailleur doesn't shift cleanly outward; if I decrease the
tension, it doesn't shift cleanly outward. I've tried different
settings on the b-tension screw, but to no avail.

Is there a solution? The bike is eight months old. I have a ten-
speed Shimano Dura Ace rear derailleur with a 12x27 Ultegra cogset.
Everything else is Ultegra.

How many miles on the chain? If close to 2k, could be time to replace it. If
the chain isn't worn but is dirty, clean & lube it.

Also check the derailleur hanger alignment. Could be that it's bent in
slightly.

And, as others have mentioned, check for kinds in the cable housings,
especially right where they enter the ferrules.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

could be the initial tension is too high when fixing the cable to the
deray, and at that time the cable adjustor is an incorrect position in
relation to that tension. the deray itself is in the correct position
when fixing, right?
the deray can be disassembled and regreased. it wasn't properly
greased as designed when it left the factory. take a look inside.
use the marine castrol from wal-it resists water runout