index shifting : not functioning



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Walter Mitty

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I have read a few articles about rear derailleur adjusting but am still unable to get my rear
shimano rsx to shift to lower gears with a single
click. In "friction" more the shift works fine. In "index" mode I need to click down twice and then
up one in order for to move down a gear.

My LBS says the cables etc are fine, and that it's probably just tiredness on my rear mechs part -
it is 9 years old now - and that the return spring isn't strong enough.

Any hints or tips? Is it the case that it's time to change rear derailleurs?

--
Walter Mitty.
 
Shifting down 2 overcomes marginal cable drag. If the cable is fine, the spring is worn out or the
derailleur is gunked up and the added drag is enough to stop it.

If the end of the cable is not frayed, you can remove the inner cable and grease or oil the end of
it and put it back and see what happens. The end oils the whole inside as it goes by. I use a 1975
tube of white lithium grease, evidently having bought too big a tube at the time.
--
Ron Hardin [email protected]

On the internet, nobody knows you're a jerk.
 
<< I have read a few articles about rear derailleur adjusting but am still unable to get my rear
shimano rsx to shift to lower gears with a single
click. In "friction" more the shift works fine. In "index" mode I need to click down twice and then
up one in order for to move down a gear.

My LBS says the cables etc are fine, and that it's probably just tiredness on my rear mechs part -
it is 9 years old now - and that the return spring isn't strong enough. >>

Disassemble the shift lever and look for worn or broken parts, specifically the "teeth" on the
indexing-ratchet-thingy.
 
"Mike Krueger" wrote
> Disassemble the shift lever and look for worn or broken parts,
specifically the
> "teeth" on the indexing-ratchet-thingy.

Wow, that takes guts! And what if he does find worn parts? Shimano doesn't sell replacement
small parts.

A WD-40 flush is probably his best option (assuming the problem is with the shifter).

Art Harris
 
"Walter Mitty" <[email protected]> wrote in message news:[email protected]...
>
> I have read a few articles about rear derailleur adjusting but am still unable to get my rear
> shimano rsx to shift to lower gears with a single
> click. In "friction" more the shift works fine. In "index" mode I need to click down twice and
> then up one in order for to move down a gear.
>
> My LBS says the cables etc are fine, and that it's probably just tiredness on my rear mechs part -
> it is 9 years old now - and that the return spring isn't strong enough.
>
> Any hints or tips? Is it the case that it's time to change rear derailleurs?

A common question here.

Sight the rear changer's cage in high gear. Get your head behind the changer and ensure the cage is
in the same plane as the chainrings. If not, align or consult your LBS. Now disconnect the shift
wire. Pedal with your right hand. With your left, press the derailleur body with your thumb up a
couple of cogs and let go. The body should shift back to the high gear smartly. When you do that
agressively the chain should go no further than high gear. Use the "H" adjusting screw to set that
limit. Now shift to low with your thumb. Hard. Use the "L" adjusting screw to set the limit so it
can go to low but no further.

Inspect the wire and casing to preclude any rust, kinks, damaged ferrules. Smear a light oil on
wires where they will run in casing and where they slide on cable giudes. Oil the casing adjuster
and screw it tight then back a turn or two. Oil the cable anchor bolt. Ensure the derailleur is
tight to the frame.

If you haven't ever, now's a good time to open your derailleur rollers and add a drop of oil. Do
them one at a time so you don't put the top roller on the bottom. Ensure the roller bolts are tight.
That's only needed once in the life of a derailleur but manufacturers no longer do that for you.

Now connect the wire, pulling it snug with your fingers with both the lever and derailleur in high
gear. Shift one click while pedalling. The chain should now be on the second cog. If it isn't quite,
the cable is too loose. Either pull it through the anchor a bit tighter and lock it again or just
turn the adjuster tighter (anticlockwise). Once in the second cog you can finely adjust the wire's
tension by looking to ensure the roller is directly under the second cog or, truly, by ear. Once the
first shift is set correctly the other gears should all fall into place unless you are using
mixed-brand equipment.

--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
 
[email protected] (Mike Krueger) brightened my day with his incisive wit when in
news:[email protected] he conjectured that:

> << > Disassemble the shift lever and look for worn or broken parts, specifically the
>> "teeth" on the indexing-ratchet-thingy.
>
> Wow, that takes guts! And what if he does find worn parts? Shimano doesn't sell replacement small
> parts. A WD-40 flush is probably his best option (assuming the problem is with the shifter). Art
> Harris >>
>
> The OP stated that his index shifter works fine in friction mode, and that the derailleur is nine
> years old--two clues that he must be using downtube shifters. STI rear shifters have no friction
> mode. Broken teeth inside the downtube shifter will cause missed shifts, slipping gears, etc. This
> is a common failure mode for worn out SIS levers. Unscrew the shifter from the shifter boss cover
> and see if little shards of metal fall out. If so, there's the problem.
>

Maybe I made a mistake in my terminology? Or maybe the date? It's certainly 8 years old though as I
bought the bike in 95 (I think..) : it's bar end shifters and they do have a friction mode. To be
honest I don't have the skills to start taking the shifter apart - but I will try and clean the
derailleur - maybe it is just gunked up.

Thanks for the advice guys.
 
Walter Mitty <[email protected]> wrote in message news:<[email protected]>...
>
> Maybe I made a mistake in my terminology? Or maybe the date? It's certainly 8 years old though as
> I bought the bike in 95 (I think..) : it's bar end shifters and they do have a friction mode. To
> be honest I don't have the skills to start taking the shifter apart - but I will try and clean the
> derailleur - maybe it is just gunked up.
>
> Thanks for the advice guys.

I have a set of 7-speed Shimano bar-ends that still work perfectly. Also, the shifter unit can't be
disassembled.

If the cables and housings are more than a year old, I'd bet that they've gotten gummy enough to
interfere with the indexing. I'd replace cables AND housing first. New SIS housing radically
improves the shifting, particularly on the long runs to the bar ends.

Jeff
 
"A Muzi" <[email protected]> brightened my day with his incisive wit when in
news:[email protected] he conjectured that:

> "Walter Mitty" <[email protected]> wrote in message news:[email protected]...
>>
>> I have read a few articles about rear derailleur adjusting but am still unable to get my rear
>> shimano rsx to shift to lower gears with a single click. In "friction" more the shift works fine.
>> In "index" mode I need to click down twice and then up one in order for to move down a gear.
>>
>> My LBS says the cables etc are fine, and that it's probably just tiredness on my rear mechs part
>> - it is 9 years old now - and that the return spring isn't strong enough.
>>
>> Any hints or tips? Is it the case that it's time to change rear derailleurs?
>
> A common question here.
>
> Sight the rear changer's cage in high gear. Get your head behind the changer and ensure the cage
> is in the same plane as the chainrings. If not, align or consult your LBS. Now disconnect the
> shift wire. Pedal with your right hand. With your left, press the derailleur body with your thumb
> up a couple of cogs and let go. The body should shift back to the high gear smartly. When you do
> that agressively the chain should go no further than high gear. Use the "H" adjusting screw to set
> that limit. Now shift to low with your thumb. Hard. Use the "L" adjusting screw to set the limit
> so it can go to low but no further.
>
> Inspect the wire and casing to preclude any rust, kinks, damaged ferrules. Smear a light oil on
> wires where they will run in casing and where they slide on cable giudes. Oil the casing adjuster
> and screw it tight then back a turn or two. Oil the cable anchor bolt. Ensure the derailleur is
> tight to the frame.
>
> If you haven't ever, now's a good time to open your derailleur rollers and add a drop of oil. Do
> them one at a time so you don't put the top roller on the bottom. Ensure the roller bolts are
> tight. That's only needed once in the life of a derailleur but manufacturers no longer do that
> for you.
>
> Now connect the wire, pulling it snug with your fingers with both the lever and derailleur in high
> gear. Shift one click while pedalling. The chain should now be on the second cog. If it isn't
> quite, the cable is too loose. Either pull it through the anchor a bit tighter and lock it again
> or just turn the adjuster tighter (anticlockwise). Once in the second cog you can finely adjust
> the wire's tension by looking to ensure the roller is directly under the second cog or, truly, by
> ear. Once the first shift is set correctly the other gears should all fall into place unless you
> are using mixed-brand equipment.
>
> --
> Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
>
>

Hi,

Thanks for the detailed reply. I omitted to say that index shipping from high to low works fine.
It's only from low to high gear that I need to "over shift".

--
Walter Mitty.
 
I had a similar problem.

I could adjust the shift l->h or h->l, but not both. There is probably some wear in my setup, and I
noticed the top pulley had a fair bit of float. I packed it out to reduce the float to about 1/4 mm
(from 1.5 ish) and it works a treat. I understand that float is there to help reduce noise etc if
the alignment is off, but plays no part in improving shift performance - is that right?

Walter Mitty wrote:
> "A Muzi" <[email protected]> brightened my day with his incisive wit when in
> news:[email protected] he conjectured that:
>
>
>>"Walter Mitty" <[email protected]> wrote in message news:[email protected]...
>>
>>>I have read a few articles about rear derailleur adjusting but am still unable to get my rear
>>>shimano rsx to shift to lower gears with a single click. In "friction" more the shift works fine.
>>>In "index" mode I need to click down twice and then up one in order for to move down a gear.
>>>
>>>My LBS says the cables etc are fine, and that it's probably just tiredness on my rear mechs part
>>>- it is 9 years old now - and that the return spring isn't strong enough.
>>>
>>>Any hints or tips? Is it the case that it's time to change rear derailleurs?
>>
>>A common question here.
>>
>>Sight the rear changer's cage in high gear. Get your head behind the changer and ensure the cage
>>is in the same plane as the chainrings. If not, align or consult your LBS. Now disconnect the
>>shift wire. Pedal with your right hand. With your left, press the derailleur body with your thumb
>>up a couple of cogs and let go. The body should shift back to the high gear smartly. When you do
>>that agressively the chain should go no further than high gear. Use the "H" adjusting screw to set
>>that limit. Now shift to low with your thumb. Hard. Use the "L" adjusting screw to set the limit
>>so it can go to low but no further.
>>
>>Inspect the wire and casing to preclude any rust, kinks, damaged ferrules. Smear a light oil on
>>wires where they will run in casing and where they slide on cable giudes. Oil the casing adjuster
>>and screw it tight then back a turn or two. Oil the cable anchor bolt. Ensure the derailleur is
>>tight to the frame.
>>
>>If you haven't ever, now's a good time to open your derailleur rollers and add a drop of oil. Do
>>them one at a time so you don't put the top roller on the bottom. Ensure the roller bolts are
>>tight. That's only needed once in the life of a derailleur but manufacturers no longer do that
>>for you.
>>
>>Now connect the wire, pulling it snug with your fingers with both the lever and derailleur in high
>>gear. Shift one click while pedalling. The chain should now be on the second cog. If it isn't
>>quite, the cable is too loose. Either pull it through the anchor a bit tighter and lock it again
>>or just turn the adjuster tighter (anticlockwise). Once in the second cog you can finely adjust
>>the wire's tension by looking to ensure the roller is directly under the second cog or, truly, by
>>ear. Once the first shift is set correctly the other gears should all fall into place unless you
>>are using mixed-brand equipment.
>>
>>--
>>Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
>>
>>
>
>
> Hi,
>
> Thanks for the detailed reply. I omitted to say that index shipping from high to low works fine.
> It's only from low to high gear that I need to "over shift".
 
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