replaced rear derailleur cable...now what.

[gabrielle]

I've had steadily worsening shifting probs over the past couple of
weeks: bike wouldn't stay in lowest gear, and tended to jump around in
the next two lowest. Went over it last night to see if I could figure out
the problem, and WOW the cable housing is shredded where it enters the
shifter. Guess that's the problem. So I replace the cable & housing.

Question 1: How tight do I make the cable? I'm having a hard time
figuring that out because it's not instantly curing my shifting issues.
Shifting is still pretty stiff, and unpredictable in the lowest gears. Is
there some magic formula I can apply to this to get the cable set up &
then go from there, as I think I may have more than one problem.

Which leads me to rather nebulous Question 2 - a) I don't *think* I have a
bent derailleur hanger (if I do, it's not obvious). However - b) the
jockey wheels don't line up vertically with the cogs on the rear cassette
in all gears. They're perfect in the lowest gear but kinda cockeyed in
the highest.

What are my next troubleshooting steps?

gabrielle (wrenchette #2)

[Tom Purvis]

gabrielle wrote:
> I've had steadily worsening shifting probs over the past couple of
> weeks: bike wouldn't stay in lowest gear, and tended to jump around in
> the next two lowest. Went over it last night to see if I could figure out
> the problem, and WOW the cable housing is shredded where it enters the
> shifter...
>
> ...Which leads me to rather nebulous Question 2 -
> a) I don't *think* I have a bent derailleur hanger (if I do,
> it's not obvious). However - b) the jockey wheels don't line up
> vertically with the cogs on the rear cassette in all gears. They're
> perfect in the lowest gear but kinda cockeyed in the highest.
>
> What are my next troubleshooting steps?

I'm betting your hanger is bent. The derailleur itself may have
been tweaked.

The symptoms that you list sound exactly like what a bent hanger
will cause. And it's really a common problem.

These are areas where it's nice to have access to fully equipped
bike workbench. Checking hanger alignment is easy with the right
tool, and you're pretty much guessing without it.

Chances are you have a replaceable hanger on your frame. You should
always have a backup for your frame. And take it with you when you
travel. It can take a while to get one, depending on the mfger, etc.

Speaking from experience, I'll say that you can spend lots of time
and money trying to adjust, replace, repair everything but the hanger
when it's bent. Check it or have a shop check it so that you can
eliminate that as a problem ASAP, before you take any other steps.

My $.02
--
Tom Purvis - http://www.arkansasvalley.net/tpurvis/
"The more you drive the less intelligent you are." -Miller, Repo Man.

[Tom Purvis]

gabrielle wrote:
> What are my next troubleshooting steps?

I meant to answer this question directly:

With rear shifting problems, a good mechanic with access to a complete
set of tools will start troubleshooting by eliminating the hanger as
a possible cause of trouble. It's the quickest thing to do, and it's
the foundation of the rear derailleur's position.

Once you can confirm that the hanger is straight, if the jockey wheels
still fail to line up then it's your derailleur.

(forgive me for replying to my own post)
--
Tom Purvis - http://www.arkansasvalley.net/tpurvis/
"The more you drive the less intelligent you are." -Miller, Repo Man.

[JD]

gabrielle wrote:
> Which leads me to rather nebulous Question 2 - a) I don't *think* I have a
> bent derailleur hanger (if I do, it's not obvious). However - b) the
> jockey wheels don't line up vertically with the cogs on the rear cassette
> in all gears. They're perfect in the lowest gear but kinda cockeyed in
> the highest.
>
> What are my next troubleshooting steps?


If the hanger is replaceable, get a new one. They're normally not too
expensive and if I remember correctly, you ave an aluminium frame and
bending that material back causes significant weakness compared to
steel.

JD

[MattB]

JD wrote:
> gabrielle wrote:
>
>>Which leads me to rather nebulous Question 2 - a) I don't *think* I have a
>>bent derailleur hanger (if I do, it's not obvious). However - b) the
>>jockey wheels don't line up vertically with the cogs on the rear cassette
>>in all gears. They're perfect in the lowest gear but kinda cockeyed in
>>the highest.
>>
>>What are my next troubleshooting steps?
>
>
>
> If the hanger is replaceable, get a new one. They're normally not too
> expensive and if I remember correctly, you ave an aluminium frame and
> bending that material back causes significant weakness compared to
> steel.
>
> JD
>

I recently replaced the hanger on my Epic and it significantly improved
shifting. I'd been having phantom shifting issues all summer.

I just had the LBS do it since they have the right tools. It was only
about $20 and a six pack.

Matt

[Shawn]

Tom Purvis wrote:
> gabrielle wrote:
>
>>I've had steadily worsening shifting probs over the past couple of
>>weeks: bike wouldn't stay in lowest gear, and tended to jump around in
>>the next two lowest. Went over it last night to see if I could figure out
>>the problem, and WOW the cable housing is shredded where it enters the
>>shifter...
>>
>>...Which leads me to rather nebulous Question 2 -
>>a) I don't *think* I have a bent derailleur hanger (if I do,
>>it's not obvious). However - b) the jockey wheels don't line up
>>vertically with the cogs on the rear cassette in all gears. They're
>>perfect in the lowest gear but kinda cockeyed in the highest.
>>
>>What are my next troubleshooting steps?
>
>
> I'm betting your hanger is bent. The derailleur itself may have
> been tweaked.
>
> The symptoms that you list sound exactly like what a bent hanger
> will cause. And it's really a common problem.
>
> These are areas where it's nice to have access to fully equipped
> bike workbench. Checking hanger alignment is easy with the right
> tool, and you're pretty much guessing without it.
>
> Chances are you have a replaceable hanger on your frame. You should
> always have a backup for your frame. And take it with you when you
> travel. It can take a while to get one, depending on the mfger, etc.
>
> Speaking from experience, I'll say that you can spend lots of time
> and money trying to adjust, replace, repair everything but the hanger
> when it's bent. Check it or have a shop check it so that you can
> eliminate that as a problem ASAP, before you take any other steps.

The same event that shredded your housing could've dinged your hanger
and derailleur too. As for how to adjust things, you should trust our
man Sheldon.
http://sheldonbrown.com/derailer-adjustment.html

Where'd you ride yesterday Tom? Susie and I were on our way to Bear
Creek when we saw you. Good ride till the Flash and Boom got too close
together.

Shawn

[Dave Dowler]

"gabrielle" > wrote in message
...
> Question 1: How tight do I make the cable? I'm having a hard time
> figuring that out because it's not instantly curing my shifting issues.
> Shifting is still pretty stiff, and unpredictable in the lowest gears. Is
> there some magic formula I can apply to this to get the cable set up &
> then go from there, as I think I may have more than one problem.

Just ask Sheldon - http://www.sheldonbrown.com/derailer-adjustment.html

If the shifting feels stiff the cable could be rubbing on a roughly cut
piece of housing. To check, first shift the bike into the largest rear cog.
Then, without pedaling, move the shifter into the highest gear. That gives
enough slack to remove the housing sections from the stops. They should
slide easily over the cable. Repair any rough feeling pieces. I always use a
little Tri-Flo in the housing. Don't forget to lube the derailleur pivot
points (8) if you haven't done that in a while.

>
> Which leads me to rather nebulous Question 2 - a) I don't *think* I have a
> bent derailleur hanger (if I do, it's not obvious). However - b) the
> jockey wheels don't line up vertically with the cogs on the rear cassette
> in all gears. They're perfect in the lowest gear but kinda cockeyed in
> the highest.
>
> What are my next troubleshooting steps?

Could also be that the bushings in the derailleur are worn. Try wiggling the
bottom of the jockey wheel assembly sideways. The more play, the less
precise your shifting will be. The best calibration for this test is to
compare yours side by side with a new drivetrain with a similar derailleur.
I don't know of any substitute for hanger alignment tool. I've dealt with
enough bent hangers that I bought my own. If sticks & crashes are a rare
occurence for you, a trip to the LBS is probably more cost efective.
http://www.pricepoint.com/detail/11933-325_PARDA2-2-Accessories-42-Tools/Park-DAG-1-Derailleur-Hanger-Alignment-Guage.htm

Dave D.

[Tom Purvis]

Shawn wrote:
> ...Where'd you ride yesterday Tom? Susie and I were on our
> way to Bear Creek when we saw you. Good ride till the Flash
> and Boom got too close together.

I was just finishing up Bear Creek-Rainbow-108-powerline-Lost Trail.
Got SOAKED during 3 or 4 miles of the Rainbow, but there was no
lightening, just really cold rain. Luckily my new rain jacket was
safe at home where it wouldn't get dirty or sweaty.

Then I clipped a sharp rock on Lost Trail and BOOM (blew out a
sidewall, and blasted slime all over an innocent pinon pine
bystander). Found my tire boot missing from the camelbak (?) and
had to use a single serving hand wipe package, which juiced out
as I aired up the tire. But it held back to the house!

It was my ride for odd luck. I've barely missed plenty of storms
and had almost no mechanicals in a long summer of good riding.
So I grinned, happily cobbled the bike together, and rode out
carefully. Good chance to dry off. Actually it was lucky that
the sidewall failed loudly. I was going to just run those tires
in the Banana Belt this weekend. If it hadn't failed I might not
have looked closely at it any time before the race.

Woo Hoo!
--
Tom Purvis - http://www.arkansasvalley.net/ tpurvis/
"The more you drive the less intelligent you are." -Miller, Repo Man.

[small change]

If your derailler hanger is bent, you may not be able to tell with a cursory
inspection. But you might: the hanger should be on an axis totally
perpendicular to the ground, parallel to the hub. If it's even a degree or
two off, typically they get bent in, you will have malfunction.
You can get down at hub level and sort of eyeball this from the back of the
bike.
Shops do have a special gizmo that they use just for checking and fixing
this. If it's minor, you can bend it back, if it's major, replacing the
hanger is what has to be done.

wrenchette #1.

P.

[D T W .../\\...]

..
" Guess that's the problem. So I replace the cable & housing.

You have a work stand, yes? The chain, sprocket, and derailleur is clean /
lubed? We can assume you replaced all of the cable housing and housing end
caps, and the last section that goes into the rear derailleur is long
enough? - see Sheldon's stuff! The shifter / derailleur casing adjusters
should be within 4 clicks of fully retracted. With the wire disconnected
from the derailleur you should be able to cycle it smoothly using the shift
lever ( a shot of silicone spray in here doesn't hurt ) and putting slight
tension on the cable with your other hand. Hook up the cable and pull it
snug by hand/pliers. Do the fine adjustments with the casing adjusters.


>> bent derailleur hanger (if I do, it's not obvious). However - b) the
> jockey wheels

(only one jockey wheel, at the cassette, the other's a tension wheel)

>
> What are my next troubleshooting steps?
>
> gabrielle (wrenchette #2)


try above and see how it goes,,,,,,,,,

--
DTW .../\.../\.../\...

I've spent most of my money on mountain biking and windsurfing.
The rest, I've just wasted

[gabrielle]

On Wed, 07 Sep 2005 08:57:07 -0700, small change wrote:

> Shops do have a special gizmo that they use just for checking and fixing
> this. If it's minor, you can bend it back, if it's major, replacing the
> hanger is what has to be done.

Just ran it down there, I'm a-ok in this dept. Yee-hah.

gabrielle

[Vee]

gabrielle wrote:
> On Wed, 07 Sep 2005 08:57:07 -0700, small change wrote:
>
> > Shops do have a special gizmo that they use just for checking and fixing
> > this. If it's minor, you can bend it back, if it's major, replacing the
> > hanger is what has to be done.
>
> Just ran it down there, I'm a-ok in this dept. Yee-hah.

Did the shop check your chain and cassette for wear? You should at
least check the chain, since it's easy. See Sheldon Brown's website
(others have linked it above) for info. The problem you describe is
nearly always the result of these things, or a combination of them:
cable too tight/loose; cable improperly clamped to derailleur;
cable/housing dirty or damaged; derailleur hanger bent; chain and
cassette wear. The derailleur itself is almost never the cause of
shifting problems, so rule out the other stuff first.

-Vee

[gabrielle]

On Wed, 07 Sep 2005 22:12:44 +0000, D T W .../\... wrote:
> You have a work stand, yes?
I have a workstand, no. :P I'm doing this in my driveway with my bike
leaning up against the fence. :) Oh, did I mention the wasps? Wah.

> The chain, sprocket, and derailleur is clean / lubed?
Check! Went over it with a toothbrush. My husband's, of course. ;)

> We can assume you replaced all of the cable housing and housing end
> caps, and the last section that goes into the rear derailleur is long
> enough? - see Sheldon's stuff!
Check! Replacing the cables + housing was the easy (fun) part.

The shifter / derailleur casing adjusters
> should be within 4 clicks of fully retracted.

Casing adjusters = the barrel adjusters on the shifter & the derailleur?

> With the wire
> disconnected from the derailleur you should be able to cycle it smoothly
> using the shift lever ( a shot of silicone spray in here doesn't hurt )
> and putting slight tension on the cable with your other hand. Hook up
> the cable and pull it snug by hand/pliers. Do the fine adjustments
> with the casing adjusters.
(see below)

>>> bent derailleur hanger (if I do, it's not obvious).
Had this checked. It's straight, but one of the screws holding it on to
the frame was loose. Like I said, more than one problem. <rme>

> try above and see how it goes,,,,,,,,,

....one hour later...
It turned out to be fairly simple - I had the cable waaaaay too loose.
The tipoff was that I couldn't get into my 3 biggest cogs with the
derailleur, but when I pulled extra tension on the cable manually, it
shifted just fine. I *really* had a hard time getting enough tension to
pull it tight enough through the cable fixing bolt - where is that extra
hand I ordered???

Once I had that solved, it took 1/2 turn of the barrel adjuster & voila,
access to all gears. :) Worked great on an around-the-neighborhood spin;
I will test it out for real on Friday's Post Canyon Happy Hour Ride. I
probably shouldn't tally up how much $$$ I save yet, eh, since I'm not
certain I'm finished.

Thanks everyone!

gabrielle

[Corvus Corvax]

gabrielle wrote:
>
> It turned out to be fairly simple - I had the cable waaaaay too loose.
> The tipoff was that I couldn't get into my 3 biggest cogs with the
> derailleur, but when I pulled extra tension on the cable manually, it
> shifted just fine. I *really* had a hard time getting enough tension to
> pull it tight enough through the cable fixing bolt - where is that extra
> hand I ordered???

Hmm. This sounds strange to me. What gear did you have it in to install
the cable (i.e., where was the shifter set)? When you thread the cable,
the shifter should be released all the way to the smallest cog, which
is the point at which the cable is loosest for a high-normal
derailleur. Then you can simply pull the cable taut, but not
super-tight, and you'll be pretty close to the correct tension. Your
description sounds almost like you had the shifter set to the biggest
cog on the rear and you tried to tension it with muscle instead of
brains ;-).

CC

[gabrielle]

On Thu, 08 Sep 2005 18:24:34 -0700, Corvus Corvax wrote:

> Hmm. This sounds strange to me. What gear did you have it in to install
> the cable (i.e., where was the shifter set)? When you thread the cable,
> the shifter should be released all the way to the smallest cog, which
> is the point at which the cable is loosest for a high-normal
> derailleur. Then you can simply pull the cable taut, but not
> super-tight, and you'll be pretty close to the correct tension.
Yeah, that's what I did. :P The original directions I had said to pull it
taut specifically only with finger pressure because using pliers will
crimp the cable, and this is BAD BAD BAD and will cause your crops to burn
& your children to die. ;) I type all day & play piano but I have no
grip strength.

Your
> description sounds almost like you had the shifter set to the biggest
> cog on the rear and you tried to tension it with muscle instead of
> brains ;-).
That is certainly a valid assumption in most circumstances. :)

gabrielle