Rear mech question - opinions needed

[Oldskoolskater]

My Deore LX mech is starting to not shift to smaller cogs
(the smallest 4) very well, and I suspect the spring is too
weak for the job as the mech has done 6000 miles. I
currently get around the problem by shifting down two clicks
and then back one! The rest of the mech looks fine, but I
guess that I will not be able to get hold of just the spring
for repair purposes? Should I get a new mech or try to get
spares? I case you were wondering, the shifting cable has
been replaced.

Cheers

Steve

[Davep]

Oldskoolskater wrote:

>My Deore LX mech is starting to not shift to smaller cogs
>(the smallest 4) very well, and I suspect the spring is too
>weak for the job as the mech has done 6000 miles. I
>currently get around the problem by shifting down two
>clicks and then back one! The rest of the mech looks fine,
>but I guess that I will not be able to get hold of just the
>spring for repair purposes? Should I get a new mech or try
>to get spares? I case you were wondering, the shifting
>cable has been replaced.
>
>Cheers
>
>Steve
>
>
Have you removed the chain and checked the movement of
the mech? Remove the cable , how does the mech feel when
moved by hand?

davep

[Anonymous]

Oldskoolskater posted ...

> My Deore LX mech is starting to not shift to smaller cogs
> (the smallest 4) very well, and I suspect the spring is
> too weak for the job as the mech has done 6000 miles. I
> currently get around the problem by shifting down two
> clicks and then back one! The rest of the mech looks fine,
> but I guess that I will not be able to get hold of just
> the spring for repair purposes? Should I get a new mech or
> try to get spares? I case you were wondering, the shifting
> cable has been replaced.
>
> Cheers
>
> Steve

I'd remove the chain and see that the mech gets full
movement, and simply needs adjustment or maybe just a damn
good clean and lubrication .. ;)

I had a similar problem once where the cage of the rear mech
had been hit while out riding and wasn't a parallelogram
anymore, so wouldn't shift up to the higher gears at all ..
it needed a replacement derailleur really, but a twist with
a set of stillsons cured it for a year or so .. ;) If this
is the case, make sure the chain return cogs are also
running correctly and in-line with the chain run.

Are you sure it's the rear mech and not the twist-grip or
shifters that are causing the problem ? If the cable is new,
as you say, be certain that it's been replaced, and works,
correctly at both ends .. ;)

--
Paul

(8(|) Homer rocks .. ;)

[Frank X]

news:c36r9o$246qh2$1@ID-137265.news.uni-berlin.de...
> Oldskoolskater posted ...
>
> > My Deore LX mech is starting to not shift to smaller
> > cogs (the smallest 4) very well, and I suspect the
> > spring is too weak for the job as the mech has done 6000
> > miles. I currently get around the problem by shifting
> > down two clicks and then back one! The rest of the mech
> > looks fine, but I guess that I will not be able to get
> > hold of just the spring for repair purposes? Should I
> > get a new mech or try to get spares? I case you were
> > wondering, the shifting cable has been replaced.
> >
> > Cheers
> >
> > Steve
>
> I'd remove the chain and see that the mech gets full
> movement, and simply needs adjustment or maybe just a damn
> good clean and lubrication .. ;)
>
> I had a similar problem once where the cage of the rear
> mech had been hit while out riding and wasn't a
> parallelogram anymore, so wouldn't shift up
to
> the higher gears at all .. it needed a replacement
> derailleur really, but
a
> twist with a set of stillsons cured it for a year or
> so .. ;)

I've found that even the slightest knock to either my
derailer or the replaceable dropout can cause it to shift
badly. This tends to mean you can adjust it ok for
particular sub ranges of gears but not for all 8 or 9 at the
same time.

I think the derailer cage is supposed to be vertical and
that any deviation from this will cause a problem (but I
could be wrong)

[Just Zis Guy]

"Oldskoolskater" <oldskoolskater@mailinator.com> wrote in message
news:e41f0780.0403160250.28ac7f1b@posting.google.com...

> My Deore LX mech is starting to not shift to smaller cogs
> (the smallest 4) very well, and I suspect the spring is
> too weak for the job as the mech has done 6000 miles.

As has mine, with no problems. It's probably adjustment
but could easily just be dirt in the pivots and stuff.
I suggest:

o Removing the mech from the bike and cleaning thoroughly o
Ditto the chain and cassette o Refitting and lubricating
with your lube of choice, especially the pivots on the
parallelogram o Adjusting as per the service instructions at
shimano.com, and o Trying again.

For the ultimate in Smooth Shifting Performance [tm]
fit a set of Tacx needle roller jockey wheels while
you're about it.

To be fair just adjusting, or lubing and adjusting would
probably work, but it's Srping and the time of shining up
the bikes is upon us (I cleaned and fettled mine on Sunday
with excellent results).

--
Guy
===
May contain traces of irony. Contents liable to settle after
posting. http://www.chapmancentral.co.uk (http://www.chapmancentral.co.uk/)

88% of helmet statistics are made up, 65% of them at
Washington University

[Oldskoolskater]

> Remove the cable , how does the mech feel when moved
> by hand?

Feels quite stiff, but I'm not sure how much tension there
should be? It may be significant, but I fitted a new chain
recently and that obviously has much less sideways play than
the worn one.

Cheers

Steve

[Dave Kahn]

oldskoolskater@mailinator.com (Oldskoolskater) wrote in message news:<e41f0780.0403160250.28ac7f1b@posting.google.com>...
> My Deore LX mech is starting to not shift to smaller cogs
> (the smallest 4) very well, and I suspect the spring is
> too weak for the job as the mech has done 6000 miles. I
> currently get around the problem by shifting down two
> clicks and then back one! The rest of the mech looks fine,
> but I guess that I will not be able to get hold of just
> the spring for repair purposes? Should I get a new mech or
> try to get spares? I case you were wondering, the shifting
> cable has been replaced.

I'd be amazed if the spring had worn out that quickly.
They should last for years and years. It's more likely to
be something else causing too much resitance. I know you
changed the cable, but if this was just the inner what
condition is the outer in? Is the shifter stiff? Are the
bearings in the mech itself stiff? If you take the mech
completely off the bike and work it in your hands you'll
have a good idea whether the spring is still strong and
whether it moves freely. You will also be able to assess
how easily the cable pulls when you operate the shifter
by itself.

--
Dave...