New Mech?

[Marc]

No matter what I do I can't get the rear mech adjusted, properly, at the momene I seem to have only
3 gears on a six gear block. I have replaced the cable, but every time I run through the sequence of
changes the cable is so slack the it fouls the mud guard.I have read Sheldon, Grime time and every
manual I can lay my hands on, I have adjusted the H & L screws up down and sideways .The mech seems
to have about 10 mm of play when pushed sideways by hand , is the mech just knackered and if so can
I now get a rear mech for something as ancient as an early 80's Galaxy with a 6 speed block?

 

[Pete Biggs]

Marc wrote:
> No matter what I do I can't get the rear mech adjusted, properly, at the momene I seem to have
> only 3 gears on a six gear block. I have replaced the cable, but every time I run through the
> sequence of changes the cable is so slack the it fouls the mud guard.I have read Sheldon, Grime
> time and every manual I can lay my hands on, I have adjusted the H & L screws up down and
> sideways .

Check cable guide under bottom bracket is not gunged up. Make sure the cable is taut in top gear, is
not frayed anywhere, and check the cable is _correctly_ routed and attached to the pinch bolt (eg.
not attached to the wrong side; might have a little groove for the cable). Then check cable housing,
ferules and cable adjusters are not mashed up or loose.

Then I would think about the shifter (gear lever - although down tube levers are so simple and
reliable that I can't imagine they'd be anything wrong with it).

Have you made any major changes, or has the indexing gradually got worse?

> The mech seems to have about 10 mm of play when pushed sideways by hand

That's a lot (depending on where that play is, and what you mean by play).

> , is the mech just knackered

Might be but I would still expect a kackered mech to index better than what you're getting.

> and if so can I now get a rear mech for something as
> ancient as an early 80's Galaxy with a 6 speed block?

Can still get some old-style mechs, but you may find a modern one designed for 7, 8 or 9sp works
fine. For a start, see: http://www.sjscycles.com/store/vIndex.htm

~PB

 

[Marc]

Pete Biggs <pLime{remove_fruit}@biggs.tc> wrote:

> Marc wrote:
> > No matter what I do I can't get the rear mech adjusted, properly, at the momene I seem to have
> > only 3 gears on a six gear block. I have replaced the cable, but every time I run through the
> > sequence of changes the cable is so slack the it fouls the mud guard.I have read Sheldon, Grime
> > time and every manual I can lay my hands on, I have adjusted the H & L screws up down and
> > sideways .
>
> Check cable guide under bottom bracket is not gunged up.

Done.

> Make sure the cable is taut in top gear,
Done.

> is not frayed anywhere,

New cable

>and check the cable is _correctly_ routed and attached to the pinch bolt (eg. not attached to the
>wrong side; might have a little groove for the cable). Then check cable housing, ferules and cable
>adjusters are not mashed up or loose.

Done, Done, done, done,
>
> Then I would think about the shifter (gear lever - although down tube levers are so simple and
> reliable that I can't imagine they'd be anything wrong with it).

Done,
>
> Have you made any major changes, or has the indexing gradually got worse?

It was getting worse
>
> > The mech seems to have about 10 mm of play when pushed sideways by hand
>
> That's a lot (depending on where that play is, and what you mean by play).

On the chaine guide, play as in the cuide can be moved 5mm in each direction ( in and out) from an
point selected by the leaver.

>
> > , is the mech just knackered
>
> Might be but I would still expect a kackered mech to index better than what you're getting.
>
> > and if so can I now get a rear mech for something as
> > ancient as an early 80's Galaxy with a 6 speed block?
>
> Can still get some old-style mechs, but you may find a modern one designed for 7, 8 or 9sp works
> fine. For a start, see: http://www.sjscycles.com/store/vIndex.htm
Ta! Will look!

 

[Pete Biggs]

Marc wrote:
>>> The mech seems to have about 10 mm of play when pushed sideways by hand
>>
>> That's a lot (depending on where that play is, and what you mean by play).
>
> On the chaine guide, play as in the cuide can be moved 5mm in each direction ( in and out) from an
> point selected by the leaver.

Just tested my mid-90's Deore XT 6sp mech on hack bike: More than 10mm of play!! (that was a
surprise!) (more play outwards than inwards) - but it still indexes well enough. So I dunno, but I
suppose it's worth trying another mech as you've tried everything else. Good luck.

~PB

 

[Jumpzkid]

"Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
news:<[email protected]>...
> Marc wrote:
> >>> The mech seems to have about 10 mm of play when pushed sideways by hand
> >>
> >> That's a lot (depending on where that play is, and what you mean by play).
> >
> > On the chaine guide, play as in the cuide can be moved 5mm in each direction ( in and out) from
> > an point selected by the leaver.
>
> Just tested my mid-90's Deore XT 6sp mech on hack bike:

no such thing mid 90s xt is 8speed mid 80s maybe. OP take off cable and chain and move mech by hand
probably a cable or housing problem. JumpZkid
--
The opinions expressed are those of the JUMPHUNTER!!!!!!!!!!!!

 

[Dave Kahn]

[email protected] (Marc) wrote in message
news:<[email protected]>...
> No matter what I do I can't get the rear mech adjusted, properly, at the momene I seem to have
> only 3 gears on a six gear block. I have replaced the cable, but every time I run through the
> sequence of changes the cable is so slack the it fouls the mud guard.

I presume you've adjusted it so that the cable is taut when it's in top gear, so where is the slack
coming from? Either the cable is slipping through the clamp at the derailleur, or the derailleur is
not moving to take up the slack. What's it like when you remove the chain and disconnect the cable
from the derailleur? It should be in the top gear position, and you should be able to push it
against the spring into the bottom gear position. When you release it it should spring back into top
gear position. The movement should be smooth with no binding or jumping.

While you have the cable disconnected from the derailleur, test how freely it moves. The lever
should be able to pull it smoothly and effortlessly through the outer cable. When you move the lever
the other way you should be able to take up the slack easily with just your fingers.

If this all seems good then with the chain back on you should check that the jockey wheel cage is
correctly fitted with the chain being held taut in all positions.

--
Dave...

 

[Marc]

Dave Kahn <[email protected]> wrote:

> [email protected] (Marc) wrote in message
> news:<[email protected]>... > No matter what I do I can't get the rear
> mech adjusted, properly, at the > momene I seem to have only 3 gears on a six gear block. I have
> replaced > the cable, but every time I run through the sequence of changes the > cable is so slack
> the it fouls the mud guard.
>
> I presume you've adjusted it so that the cable is taut when it's in top gear, so where is the
> slack coming from?

When I cylce from top to bottom and back, when the lever is in top the chain is only halfway.

> Either the cable is slipping through the clamp at the derailleur, or the derailleur is not moving
> to take up the slack. What's it like when you remove the chain and disconnect the cable from the
> derailleur? It should be in the top gear position, and you should be able to push it against the
> spring into the bottom gear position. When you release it it should spring back into top gear
> position. The movement should be smooth with no binding or jumping.

Will try it tonight

> > While you have the cable disconnected from the
derailleur, test how > freely it moves. The lever should be able to pull it smoothly and >
effortlessly through the outer cable. When you move the lever the > other way you should be able to
take up the slack easily with just > your fingers.

Cable slips nice and easily, new cable oiled with a hydraulic oiler.

> >
If this all seems good then with the chain back on you should check > that the jockey wheel cage is
correctly fitted with the chain being > held taut in all positions. > > -- > Dave...

Thanks, will have another look before I just dump it down the bike shop for them to sort out.

-- Marc T Shirts, Sweatshirts, polo shirts, banners, signs,decals, stickers etc for clubs and
associations of all types http://www.jaceeprint.demon.co.uk/

 

[Pete Biggs]

Jumpzkid wrote:

>> Just tested my mid-90's Deore XT 6sp mech on hack bike:
>
> no such thing mid 90s xt is 8speed mid 80s maybe.

On second thoughts, it's probably early 90's (I can't remember what year I bought it), and it
doesn't say what "speed" it is, but I used it with 6 (now with Campag 8).

~PB