rear derailler indexing a bit off

[Stephen Patterson]

I've recently taken the bike's wheels off a couple of times to shift it in the
back of the car (went up to Northumberland for a few days trundling), after this
the indexing on the back derailler isn't lining up right. Its Shimano geared
with 7 on the rear. The shifter lines up fine for the 2 cogs nearest to &
furthest from the wheel. On the middle gears the chain lines up reasonably but
you can hear it clinking against the cogs and it tends to change up a gear if
you have to stomp the pedals.

I've looked at the Sheldon bikes site but the normal adjustments (cable tension,
high/low screws) only sound right if the shifter's misaligning the same amount
on all gears.

any suggestions, or is it LBS time. Didn't even have indexing on my last bike

--
Stephen Patterson :: [email protected] :: http://patter.mine.nu/
GPG: E3E8E974 :: Jabber: [email protected]
"At night, the razor weasels come."

 

[Rob Morley]

In article <[email protected]>
Stephen Patterson <[email protected]> wrote:
> I've recently taken the bike's wheels off a couple of times to shift it in the
> back of the car (went up to Northumberland for a few days trundling), after this
> the indexing on the back derailler isn't lining up right. Its Shimano geared
> with 7 on the rear. The shifter lines up fine for the 2 cogs nearest to &
> furthest from the wheel. On the middle gears the chain lines up reasonably but
> you can hear it clinking against the cogs and it tends to change up a gear if
> you have to stomp the pedals.
>
> I've looked at the Sheldon bikes site but the normal adjustments (cable tension,
> high/low screws) only sound right if the shifter's misaligning the same amount
> on all gears.
>
> any suggestions, or is it LBS time. Didn't even have indexing on my last bike
>
>
For it to have suddenly gone out of adjustment you've probably either
bent the derailleur or snagged the cable on something. You could try
tightening the cable with the adjuster, after checking that the pinch
bolt is properly tightened. If you have a good eye you may be able to
see if the derailleur hanger or the mech itself is bent, and tweak it
back into place. Otherwise a good LBS will have a hanger alignment tool
to check it's straight.

 

[Paul - xxx]

Rob Morley came up with the following;:
> In article <[email protected]>
> Stephen Patterson <[email protected]> wrote:
>> I've recently taken the bike's wheels off a couple of times to shift it
>> in the back of the car (went up to Northumberland for a few days
>> trundling), after this the indexing on the back derailler isn't lining
>> up right. Its Shimano geared with 7 on the rear. The shifter lines up
>> fine for the 2 cogs nearest to & furthest from the wheel. On the middle
>> gears the chain lines up reasonably but you can hear it clinking against
>> the cogs and it tends to change up a gear if you have to stomp the
>> pedals.
>>
>> I've looked at the Sheldon bikes site but the normal adjustments (cable
>> tension, high/low screws) only sound right if the shifter's misaligning
>> the same amount on all gears.
>>
>> any suggestions, or is it LBS time. Didn't even have indexing on my last
>> bike
>>
>>
> For it to have suddenly gone out of adjustment you've probably either
> bent the derailleur or snagged the cable on something. You could try
> tightening the cable with the adjuster, after checking that the pinch
> bolt is properly tightened. If you have a good eye you may be able to
> see if the derailleur hanger or the mech itself is bent, and tweak it
> back into place. Otherwise a good LBS will have a hanger alignment tool
> to check it's straight.

I'd agree with Rob, bent derailleur hanger, cage or bent and kinked cable.

--
Paul ...
(8(|) Homer Rules ..... Doh !!!

 

[John]

"Rob Morley" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>
> Stephen Patterson <[email protected]> wrote:

>>
> For it to have suddenly gone out of adjustment you've probably either
> bent the derailleur or snagged the cable on something. You could try
> tightening the cable with the adjuster, after checking that the pinch
> bolt is properly tightened. If you have a good eye you may be able to
> see if the derailleur hanger or the mech itself is bent, and tweak it
> back into place. Otherwise a good LBS will have a hanger alignment tool
> to check it's straight.

Can they fix a bent mech? It has always seemed to me that even the slightest
imperfection in a rear mech can throw it off. I've always just bought new
ones.

 

[Rob Morley]

In article <[email protected]>
John <[email protected]> wrote:
>
> "Rob Morley" <[email protected]> wrote in message
> news:[email protected]...
> > In article <[email protected]>
> > Stephen Patterson <[email protected]> wrote:
>
> >>
> > For it to have suddenly gone out of adjustment you've probably either
> > bent the derailleur or snagged the cable on something. You could try
> > tightening the cable with the adjuster, after checking that the pinch
> > bolt is properly tightened. If you have a good eye you may be able to
> > see if the derailleur hanger or the mech itself is bent, and tweak it
> > back into place. Otherwise a good LBS will have a hanger alignment tool
> > to check it's straight.
>
> Can they fix a bent mech? It has always seemed to me that even the slightest
> imperfection in a rear mech can throw it off. I've always just bought new
> ones.
>
>
Depends - sometimes it's easy to tweak a bent cage so it works well
enough, but it's not worth investing much effort because it will
probably never be spot-on and replacement is quick and easy.

 

[mb]

Stephen Patterson wrote:

> I've recently taken the bike's wheels off a couple of times to shift
> it in the back of the car (went up to Northumberland for a few days
> trundling), after this the indexing on the back derailler isn't
> lining up right. Its Shimano geared with 7 on the rear. The shifter
> lines up fine for the 2 cogs nearest to & furthest from the wheel. On
> the middle gears the chain lines up reasonably but you can hear it
> clinking against the cogs and it tends to change up a gear if you
> have to stomp the pedals.
>
> I've looked at the Sheldon bikes site but the normal adjustments
> (cable tension, high/low screws) only sound right if the shifter's
> misaligning the same amount on all gears.
>
> any suggestions, or is it LBS time. Didn't even have indexing on my
> last bike


I'll take a guess at:
The smallest and largest cogs are OK 'cos that's where the rear mech
travel screws are stopping the thing.
The rear mech prolly just needs a tweak on the cable adjuster to set
things up OK.
Put the chain on the third cog and use the cable adjuster to line it up.

--
Mike