Dura-Ace 10 shifting problem

Quoted message said:

'04 Trek OCLV with Dura-Ace 10, 53-39 & 11-23.
The drivetrain has about 500 miles on it, and
the chain was cleaned & re-lubed about a week
ago.

What type of lube are you using? If wax, try something else. Wax-type lubes
can give trouble across the smaller cogs

Quoted message said:

The RD hesitates significantly upshifting from
53-14 to 53-13, and somewhat from 53-13 to 53-12.
It shifts cleanly on a workstand, but on the road
or on a trainer, the hesitation appears. All
other gears shift fine, road or workstand.

Try moving the "B" tension adjustment out as far as it goes, allowing the
derailleur to wrap the cogs a bit more.

Quoted message said:

LBS adjusted everything several times, and when
those two shifts are better, everything else is
worse. Conversely, when it's adjusted so all other
shifts are clean, those two are a problem again.
They spent about 1/2 hour last night hunched over
it while I rode it on a trainer, and couldn't fix
it.

In general, such problems are most often caused by even the slightest
resistance in the cable/housing interface. Ah, that bike has a stainless
steel bottom bracket cable guide, which can add friction to the interface
between it and the cable. Try getting some lube down there and see if it has
any effect.

Quoted message said:

They checked the hanger alignment, and it was
fine. Likewise, they say all the components (RD,
chain, cassette) look fine as well. None of the
cogs are on backward. Today they are going to
tear it apart to check it all out in more detail.

Before doing anything heroic, simply swap an entire wheel from another bike
into it and make sure the problem is still there. That's the easiest way to
rule out a cog problem.

Quoted message said:

In the meantime, and in case they don't find
anything, I was wondering if anybody has seen
something like this where gears in the middle of
a cassette don't shift cleanly, and has any ideas.

Pretty common, but as I mentioned, it's usually related to a cable glitch.
Usually, but not always. Good luck-

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
IMBA, BikesBelong, NBDA member

Quoted message said:

'04 Trek OCLV with Dura-Ace 10, 53-39 & 11-23.
The drivetrain has about 500 miles on it, and
the chain was cleaned & re-lubed about a week
ago.

What type of lube are you using? If wax, try something else. Wax-type lubes
can give trouble across the smaller cogs

Quoted message said:

The RD hesitates significantly upshifting from
53-14 to 53-13, and somewhat from 53-13 to 53-12.
It shifts cleanly on a workstand, but on the road
or on a trainer, the hesitation appears. All
other gears shift fine, road or workstand.

Try moving the "B" tension adjustment out as far as it goes, allowing the
derailleur to wrap the cogs a bit more.

Quoted message said:

LBS adjusted everything several times, and when
those two shifts are better, everything else is
worse. Conversely, when it's adjusted so all other
shifts are clean, those two are a problem again.
They spent about 1/2 hour last night hunched over
it while I rode it on a trainer, and couldn't fix
it.

In general, such problems are most often caused by even the slightest
resistance in the cable/housing interface. Ah, that bike has a stainless
steel bottom bracket cable guide, which can add friction to the interface
between it and the cable. Try getting some lube down there and see if it has
any effect.

Quoted message said:

They checked the hanger alignment, and it was
fine. Likewise, they say all the components (RD,
chain, cassette) look fine as well. None of the
cogs are on backward. Today they are going to
tear it apart to check it all out in more detail.

Before doing anything heroic, simply swap an entire wheel from another bike
into it and make sure the problem is still there. That's the easiest way to
rule out a cog problem.

Quoted message said:

In the meantime, and in case they don't find
anything, I was wondering if anybody has seen
something like this where gears in the middle of
a cassette don't shift cleanly, and has any ideas.

Pretty common, but as I mentioned, it's usually related to a cable glitch.
Usually, but not always. Good luck-

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
IMBA, BikesBelong, NBDA member

Mike Jacoubowsky/Chain Reaction Bicycles wrote:

Thanks for the reply, Mike.

Quoted message said:

What type of lube are you using? If wax, try something else. Wax-type lubes
can give trouble across the smaller cogs

Pro Link chain lube. Their web site says it contains no
solids like Teflon, wax, moly, graphite or plastic.
http://www.progoldmfr.com/products/prolink.html

Quoted message said:

Try moving the "B" tension adjustment out as far as it goes, allowing the
derailleur to wrap the cogs a bit more.

Yeah, that's one of the things the LBS did.

Quoted message said:

In general, such problems are most often caused by even the slightest
resistance in the cable/housing interface. Ah, that bike has a stainless
steel bottom bracket cable guide, which can add friction to the interface
between it and the cable. Try getting some lube down there and see if it has
any effect.

Ah, that's one thing they didn't do. Any specific
recommendations, since that's one of the most likely
places to attract gunk?

Quoted message said:

Before doing anything heroic, simply swap an entire wheel from another bike
into it and make sure the problem is still there. That's the easiest way to
rule out a cog problem.

They said they were going to work on it first thing today,
so if they haven't done that already, it's too late by now. :-)

Quoted message said:

Pretty common, but as I mentioned, it's usually related to a cable glitch.
Usually, but not always. Good luck-

Thanks!

Larry Coon
University of California

Quoted message said:

Quoted message said:

In general, such problems are most often caused by even the slightest
resistance in the cable/housing interface. Ah, that bike has a stainless
steel bottom bracket cable guide, which can add friction to the interface
between it and the cable. Try getting some lube down there and see if it
has
any effect.

Ah, that's one thing they didn't do. Any specific
recommendations, since that's one of the most likely
places to attract gunk?

Yep, it's a gunky area, but I use plain old gunky Phil on mine. Looks a mess
after a while, but works. Some use teflon tubes over the cables, but that
doesn't work quite as well as grease.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
IMBA, BikesBelong, NBDA member

Larry-<< Conversely, when it's adjusted so all other
shifts are clean, those two are a problem again.
They spent about 1/2 hour last night hunched over >><BR><BR>

Der hanger is what I would look at. Next would be how smoothly the inner wire
moves in the housing. Change it to 5mm and see if that helps, new ferrules,
well trimmed housing. Sounds like the inner wire is draggy when upshifting to
the smallest gears,

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

<< Next would be how smoothly the inner wire
moves in the housing. Change it to 5mm and see if that helps, new ferrules,
well trimmed housing. Sounds like the inner wire is draggy when upshifting to
the smallest gears,

Peter Chisholm >>

Agree. I use 5mm shift housing on my Dura Ace 9sp system. The reduction in
cable friction is so obvious, I can't understand for the life of me why Shimano
spec's 4mm housing in the first place. What, is it 10 grams lighter?

Qui si parla Campagnolo said:

Der hanger is what I would look at.

The hanger was one of the first things they checked, and it
was fine (they did it in front of me, so I can verify that
it was good).

Quoted message said:

Next would be how smoothly the inner wire
moves in the housing. Change it to 5mm and see if that helps, new ferrules,
well trimmed housing. Sounds like the inner wire is draggy when upshifting to
the smallest gears,

Not all the smallest gears, though -- 12-to-11 is fine.

LBS greased the BB cable guide and replaced the cable.
They also rebuilt the RD, lengthened the chain by one
link, and tore apart/cleaned/assembled/lubed it all.
They got it better, but it was still doing it when I
rode it in the parking lot. Another 1/2 hour riding
in the shop on the trainer (I'm getting more miles there
than on the road this week) and they got it so it was
-pretty- good. I'm going to do my first real ride with
it in an hour or so, and I'll report back to them.

Per Mike's suggestion I asked if we could swap out the
wheel with one of theirs, but they didn't have a 7800
cassette in the shop. (!) They did throw my cassette
onto a Race-Lite wheel, and as expected, the problem
didn't go away. One thing they did notice was that the
cassette was digging into the freehub body a little bit
(all that massive power in my pedal stroke, I guess...),
but since nothing changed using their wheel, they didn't
think it was causing the problem. They said they'd have
a 7800 cassette in the shop by Monday, and could try
swapping it then.

Thanks for the suggestion about 5mm housing -- I'll bring
it up to them.

Any chance it could be the lever? The brought up the
possibility, but at the same time said it was very
unlikely.

Larry Coon
University of California

Mike Jacoubowsky/Chain Reaction Bicycles said:

Yep, it's a gunky area, but I use plain old gunky Phil on mine. Looks a mess
after a while, but works. Some use teflon tubes over the cables, but that
doesn't work quite as well as grease.

See my reply to Peter for the rest of the story, but
I have one additional question. It still has the steel
guide that came stock on the bike. The DA STI came with
a plastic guide -- would switching to that one help?

Larry Coon
University of California