Help: chain rub... chainline problem?

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

Quoted message said:

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

Thanks so much!

C

On a ride a couple weeks ago I noticed the same thing with my Chorus
crankset. I put on the little 39 ring for the abundant hills on the
ride. 53 ring stayed the same. Chain caught slightly on the 53 ring
when in the small cog in back. 13-28 cassette. So when the ride was
over, I put the wonderful 42 ring back on. It does not catch on the
big ring when using the smallest cog in back. Not that I try to use
the small-small combination, but sometimes you do have to use it to
keep your position in the pack.

It's weird that I do not get any chain rub with my original Chorus crankset.
What good is a 10 speed system when you can't use 20-30% of the gears
(without rubbing)???

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Not do that. This is called "cross-chaining", and is considered a bad
idea. It increases the rate of chain wear for one thing.

Here's what Shimano has to say about running in the small front
sprocket of a DA double while using any of the three smallest rears:

When the chain is in the position shown in the
illustration, the chain may contact the front
chainrings or front derailleur and generate
noise. If the noise is a problem, shift the chain
onto the next-larger rear sprocket or the one
after.

Quoted message said:

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

If this wasn't a DA, and had a conventional BB, I'd say that you could
try swapping out to a BB that was wider...but you don't have that
option. Given that the Campy crank didn't have this issue, I'd go
back to the Campy, or not cross-chain. Swapping chains is unlikely to
help IMO.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub...

That's what it would take, yes, or else a larger small ring or a smaller
large ring (neither cheap, perhaps not desirable). Or a frame with
longer chainstays.

I have tried to torque the BB cups with less

Quoted message said:

force, [..] loosen the crankarm bolts a little
to maybe get more separation between the 2 rings....

These are both bad ideas that can cause serious problems in the long
run, and won't help as you found out. Tighten those things back up
before you toast something.

Not sure how your BB fits (internal or external bearing). If it's the
old standard internal, put a shim between the right cup and the frame,
and *hope* there's enough clearance on the other side of the bottom
bracket to get things tightened down (in the old days, enough room for
the adjustable cup lock ring).

Alternately, get a different bottom bracket with adjustable chainline
(perhaps not cheap). This is the reason I love my (discontinued) Campy
Athena BBs.

Otherwise, don't use those two cogs with the small ring. With a 12-25
cassette, some of the big cogs/big ring combos should give similar
gearing. [I told the doctor "It hurts when I do this." He replied,
"Don't do that."]

Yes, it's a nuisance. Sorry. I suppose you could put on a triple BB,
but that would probably solve one problem and cause another. Not sure
if double front changers can reach out that far, and your big-big combos
would be noisier.

Doubt changing chains would help. Sorry no other magic tricks in my
pocket for this one.

Good luck,
Mark Janeba

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

It is not a 'problem', it is the result of 10 cogs(gotta go somewhere)
and lots of pins and ramps on the big ring. It is NORMAL, do not
sacrifice your proper chainline for this non-problem.

Quoted message said:

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

Thanks so much!

C

Mark Janeba said:

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub...

That's what it would take, yes, or else a larger small ring or a smaller
large ring (neither cheap, perhaps not desirable). Or a frame with
longer chainstays.

I have tried to torque the BB cups with less

Quoted message said:

force, [..] loosen the crankarm bolts a little
to maybe get more separation between the 2 rings....

These are both bad ideas that can cause serious problems in the long
run, and won't help as you found out. Tighten those things back up
before you toast something.

Not sure how your BB fits (internal or external bearing). If it's the
old standard internal, put a shim between the right cup and the frame,
and *hope* there's enough clearance on the other side of the bottom
bracket to get things tightened down (in the old days, enough room for
the adjustable cup lock ring).

Alternately, get a different bottom bracket with adjustable chainline
(perhaps not cheap). This is the reason I love my (discontinued) Campy
Athena BBs.

Otherwise, don't use those two cogs with the small ring. With a 12-25
cassette, some of the big cogs/big ring combos should give similar
gearing. [I told the doctor "It hurts when I do this." He replied,
"Don't do that."]

Yes, it's a nuisance. Sorry. I suppose you could put on a triple BB,
but that would probably solve one problem and cause another. Not sure
if double front changers can reach out that far, and your big-big combos
would be noisier.

Doubt changing chains would help. Sorry no other magic tricks in my
pocket for this one.

Good luck,
Mark Janeba

" Everytime I accelerate in my car, with a manual transmission, from a
stop light when in 3rd gear, the car bucks and makes noise and stalls.
How can I fix this problem. "

As I said, it is not a problem, it is normal and chainline should not
be mucked with. Shift into the big ring and up the cogset for the same
ratio....

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Instruct the rider to stop doing that.

Ron

Quoted message said:

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

Thanks so much!

C

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

Thanks so much!

C

On a ride a couple weeks ago I noticed the same thing with my Chorus
crankset. I put on the little 39 ring for the abundant hills on the
ride. 53 ring stayed the same. Chain caught slightly on the 53 ring
when in the small cog in back. 13-28 cassette. So when the ride was
over, I put the wonderful 42 ring back on. It does not catch on the
big ring when using the smallest cog in back. Not that I try to use
the small-small combination, but sometimes you do have to use it to
keep your position in the pack.

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

Quoted message said:

Chuck Liu said:

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

Quoted message said:

[email hidden] wrote:
> When I am in the small front chain ring and the smallest rear gear,
> the
> chain rubs the inside of the large front chain ring. What can I do to
> eliminate this problem?
>
> Here is my setup..
> Crankset: Dura Ace 10 speed double 39/53
> Cassette: Campagnolo Chorus 10 speed 12-25
> Chain: Mavic 10 speed chain
> Wheels: Mavic Ksyrium Elite
>
> The rest of the drivetrain is Campy 10spd.
>
> I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
> Ace crankset. At this point, the 2 biggest rear gears is unusable
> when
> I am in the small front ring. Other than switching back to the Chorus
> crankset or other cranks such as FSA or TA, what can I try to lessen
> this issue? I think I need to move the right crankarm further out to
> eliminate this rub... I have tried to torque the BB cups with less
> force, cleaned the chain completely, loosen the crankarm bolts a
> little
> to maybe get more separation between the 2 rings.... None of these
> tweaks work. Please help? Next thing that I will do is to change the
> chain (Connex), but I doubt it would work as the Mavic and the Connex
> has similar widths upon visual inspection....
>
> Thanks so much!
>
> C

On a ride a couple weeks ago I noticed the same thing with my Chorus
crankset. I put on the little 39 ring for the abundant hills on the
ride. 53 ring stayed the same. Chain caught slightly on the 53 ring
when in the small cog in back. 13-28 cassette. So when the ride was
over, I put the wonderful 42 ring back on. It does not catch on the
big ring when using the smallest cog in back. Not that I try to use
the small-small combination, but sometimes you do have to use it to
keep your position in the pack.

It's weird that I do not get any chain rub with my original Chorus
crankset.
What good is a 10 speed system when you can't use 20-30% of the gears
(without rubbing)???

10%. 20 gears total. Eliminate the small-small and big-big and you
have 18 usable gears. 18/20=90%. 10% of your 10 speed double ring
bike gears are not used. 100% improvement when you compare it to the
old 5 speed doubles with 10 gears total. Eliminate the small-small and
big-big and you have 8 usable gears left. 20% waste. You can of
course shift into these forbidden small-small and big-big gears when
absolutely needed. But as already mentioned, the small-small and
big-big are certainly duplicates of the other 90% usable gears. The
small-small is the same as the big ring and 1 or 2 or 3 down from the
biggest cog. The big-big is the same as the small ring and 1 or 2 or 3
up from the smallest cog.

I have 2 gears rubbing and a third one partially rubbing. I have never
experienced this with the old 9 speed bikes.... hmmm....

RonSonic <[email hidden]> wrote in
news:[email hidden]:

Quoted message said:

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Instruct the rider to stop doing that.

Ron

I say ditch the FD and carry salad tongs. you might still catch a little on
the ramps & pins, but there won't be any cage rubbing.

When I adjust my brake pads up high so they grab on the tire (because the
rubber has a higher friction coefficient than the rim), I get flats. Why is
that?

Because something can be done, doesn't mean it should. Old farts telling
you not to cross-chain should be taken as good advice. Beyond chain rub, I
killed my old Superbe Tech rear mech by cross-chaining. The internal
parallel linkage broke from the stress of the chain angle, and the cage
went into the spokes. Fortunately, I was starting up a hill (small-small)
so I was only doing about 6mph and didn't tear off the hanger.

Bad mojo, that cross-chaining.

Chuck Liu said:

It's weird that I do not get any chain rub with my original Chorus crankset.
What good is a 10 speed system when you can't use 20-30% of the gears
(without rubbing)???

Check the available ratios, and there's a good chance that you will
find that there are close matches for the S/S, S/S+1 and S/S+2
combinations which use the large ring instead. The point of having
the extra sprockets is multifold; importance of any given factor
varies with the rider. Often cited is the availability of closer
ratios to reduce cadence variance when shifting through the gears
during acceleration. Most combinations have overlap in the ratios
available with the big and small front sprockets. Generally unstated
as a reason for having a 10s cassette, but important to marketers, is
the "I must have this!" factor that is present with any numerically
"superior" option for a significant segment of the market.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Chuck Liu said:

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

Quoted message said:

Quoted message said:

When I am in the small front chain ring and the smallest rear gear, the
chain rubs the inside of the large front chain ring. What can I do to
eliminate this problem?

Here is my setup..
Crankset: Dura Ace 10 speed double 39/53
Cassette: Campagnolo Chorus 10 speed 12-25
Chain: Mavic 10 speed chain
Wheels: Mavic Ksyrium Elite

The rest of the drivetrain is Campy 10spd.

I swapped out the 170 Chorus crankset in favor of the shorter 165 Dura
Ace crankset. At this point, the 2 biggest rear gears is unusable when
I am in the small front ring. Other than switching back to the Chorus
crankset or other cranks such as FSA or TA, what can I try to lessen
this issue? I think I need to move the right crankarm further out to
eliminate this rub... I have tried to torque the BB cups with less
force, cleaned the chain completely, loosen the crankarm bolts a little
to maybe get more separation between the 2 rings.... None of these
tweaks work. Please help? Next thing that I will do is to change the
chain (Connex), but I doubt it would work as the Mavic and the Connex
has similar widths upon visual inspection....

Thanks so much!

C

On a ride a couple weeks ago I noticed the same thing with my Chorus
crankset. I put on the little 39 ring for the abundant hills on the
ride. 53 ring stayed the same. Chain caught slightly on the 53 ring
when in the small cog in back. 13-28 cassette. So when the ride was
over, I put the wonderful 42 ring back on. It does not catch on the
big ring when using the smallest cog in back. Not that I try to use
the small-small combination, but sometimes you do have to use it to
keep your position in the pack.

It's weird that I do not get any chain rub with my original Chorus crankset.
What good is a 10 speed system when you can't use 20-30% of the gears
(without rubbing)???

10%. 20 gears total. Eliminate the small-small and big-big and you
have 18 usable gears. 18/20=90%. 10% of your 10 speed double ring
bike gears are not used. 100% improvement when you compare it to the
old 5 speed doubles with 10 gears total. Eliminate the small-small and
big-big and you have 8 usable gears left. 20% waste. You can of
course shift into these forbidden small-small and big-big gears when
absolutely needed. But as already mentioned, the small-small and
big-big are certainly duplicates of the other 90% usable gears. The
small-small is the same as the big ring and 1 or 2 or 3 down from the
biggest cog. The big-big is the same as the small ring and 1 or 2 or 3
up from the smallest cog.