Servicing older Shimano 8sp STI

Greg said:

I have a couple of sets of 600 Ultegra 8sp STI levers from the early to
mid 90's. They have both seen thousands of miles and have spent the
last 4 or 5 years in a box. I am building a "beater" bike for nasty
weather riding and trying to piece it together with stuff I have,
including these shifters. They seem to downshift fine, but the shifter
doesn't always engage properly on up-shifts and I need to throw the
lever several times for the mechanism to "catch" and engage the
derailleur. If I apply a light pulling tension on the cable with my
other hand as I shift, it seems to engage more reliably. I seem to
remember an issue with either this model of shifter, the derailleur, or
both. I can't seem to recall if these are serviceable or disposable.

Can any of you fine folks share any tips on servicing, repairing or
just making them work a little better?

TIA.
Greg

Like all STI, they are not repairable. You could try to flush well with
a good spray lube, that may help, but when they 'break', they are done
and in spite of those who say ya can take them apart and repair them,
no parts available, never has been. They have been throw away since the
first model. Very clever of shimano, they fail and upgrade of other
parts is the only option....BTW, I just overhauled a pair of first
generation ERGO, from 1991, the other day....

Greg said:

I have a couple of sets of 600 Ultegra 8sp STI levers from the early to
mid 90's. They have both seen thousands of miles and have spent the
last 4 or 5 years in a box. I am building a "beater" bike for nasty
weather riding and trying to piece it together with stuff I have,
including these shifters. They seem to downshift fine, but the shifter
doesn't always engage properly on up-shifts and I need to throw the
lever several times for the mechanism to "catch" and engage the
derailleur. If I apply a light pulling tension on the cable with my
other hand as I shift, it seems to engage more reliably. I seem to
remember an issue with either this model of shifter, the derailleur, or
both. I can't seem to recall if these are serviceable or disposable.

Can any of you fine folks share any tips on servicing, repairing or
just making them work a little better?

TIA.
Greg

They're generally disposable but it's mostly because nobody supplies
replacement parts for them. In my experience, the thing that usually
breaks are certain eensy little springs. I would guess wildly that
neither of yours actually have any broken parts.

I'm not an expert in STI resuscitation but I've gotten more life out of
at least one pair of flat bar STI's having problems similar to what you
describe by taking the more superficial parts off to get access to the
main guts of the shifter and lubing everything. Most or all Shimano
shifters seem to be designed to have a fairly well sealed-off "stack"
of parts that do the actual shifting, which are accessible by removing
the covers, topcaps, etc. The only road STI surgery I've done was on
some RSX's and it was a while ago, but I know that in general they were
like this as well. You can dismantle things more fully for cleaning if
you wish - if you have a system to remember how to put it all back
together right, it's not really as bad as it's reputed to be.

here here!

I've attempted repair on several different shimano index click shifting
systems. Mostly out of curiosity with little hope of success.

1: the grease shimano uses tends to get hard and sticky over time.
That can interfere with the clicking and shifting. Start with a spray
solvent, like wd40 and shoot the spray inside alot. Repeat. Try
shifing a bunch to try to work the crud out. After waiting a couple of
days for the solvent to drip out or disvole, spray in a decent chain
lube. Lube regularly.

2: no parts available unless you have a spare unit to canabilize.

3: The early 8-speed design (600/ultegra/dura ace) a real bugger to
reassemble. Okay, iv'e never succeded. I did find the reason for
failure, a pin slide out of place. Easly reset, just impossible to
reassemble.

4: The 1999+ mostly plastic ultegra 9 speed design just wears out
quick. I did manage to reassemble it. Nothing to replace See #2.
These need lube! Once they start to act up, it's all over. Lube yours
now. This is the same model that has the rattle in the nose cone. The
1999 ultegra design is still around.

5: STX mtb flat bar model. Failed due to grease petrifiation. Took it
all a part only to find that #1 would have worked just fine. The rapid
fire design is much easier to reassemble than the sti but you don't
have to. See #1.

Greg said:

I have a couple of sets of 600 Ultegra 8sp STI levers from the early
to mid 90's. They have both seen thousands of miles and have spent
the last 4 or 5 years in a box. I am building a "beater" bike for
nasty weather riding and trying to piece it together with stuff I
have, including these shifters. They seem to downshift fine, but the
shifter doesn't always engage properly on up-shifts and I need to
throw the lever several times for the mechanism to "catch" and engage
the derailleur. If I apply a light pulling tension on the cable with
my other hand as I shift, it seems to engage more reliably. I seem to
remember an issue with either this model of shifter, the derailleur,
or both. I can't seem to recall if these are serviceable or
disposable.

Can any of you fine folks share any tips on servicing, repairing or
just making them work a little better?

Yes. To me it seems that not only is your shifter gummed up, but it seems
that your cables and housing may be gummed up and draggy, too.
Replacement is probably not necessary.

First, using a spray lube, get lube way into the innards of the shifter.
Actuate the shifter many, many, many times until the fumes begin to make you
lightheaded. Wait. Actuate the shifter again. Wait. Repeat until it
begins working well again or until you get frustrated.

Next, consider installing new cables and housing, or lubing your existing
cables, which will allow the derailleur to transmit more tension on the
cable all the way to the shifter instead of wasting it on overcoming static
friction inside the housing. Try lubing your cables first, and then seeing
how it works.

If it doesn't, the next step involves freeing up the derailleur so that the
spring tension of the derailleur can work its best at tensioning the cables.
Spray WD-40/GT-85 into the pivot points of the derailleur, where the two
plates of the parallelogram connect to the knuckles. Shift into the hardest
gear, and then, with your hands off the shifters, manually push the
derailleur all the way across the cog range while pedaling. Alternatively,
you can take the rear wheel out and just actuate the derailleur manually
without having to endure all the noise and wear of actually shifting. If
you use this alternate method, unscrew the limit screws so that you're
actuating the derailleur past its required high limit. This ensures that
when the wheel is actually in the dropouts, the derailleur will make it all
the way out to the smallest cog without corrosion/dirt/sand/crud resistance.
Along the same lines, make sure that you pull on the derailleur outwards,
too (the same direction the spring pulls it). Actuate the derailleur 20,
30, 100 times until it begins to move freely, or at least more freely.
Flush the pivots regularly. Put the wheel back in if you took it out. Test
ride. Report back here... we're interested to know.

--
Phil, Squid-in-Training

Phil said:

Greg said:

I have a couple of sets of 600 Ultegra 8sp STI levers from the early
to mid 90's. They have both seen thousands of miles and have spent
the last 4 or 5 years in a box. I am building a "beater" bike for
nasty weather riding and trying to piece it together with stuff I
have, including these shifters. They seem to downshift fine, but the
shifter doesn't always engage properly on up-shifts and I need to
throw the lever several times for the mechanism to "catch" and engage
the derailleur. If I apply a light pulling tension on the cable with
my other hand as I shift, it seems to engage more reliably. I seem to
remember an issue with either this model of shifter, the derailleur,
or both. I can't seem to recall if these are serviceable or
disposable.

Can any of you fine folks share any tips on servicing, repairing or
just making them work a little better?

Yes. To me it seems that not only is your shifter gummed up, but it seems
that your cables and housing may be gummed up and draggy, too.
Replacement is probably not necessary.

First, using a spray lube, get lube way into the innards of the shifter.
Actuate the shifter many, many, many times until the fumes begin to make you
lightheaded. Wait. Actuate the shifter again. Wait. Repeat until it
begins working well again or until you get frustrated.

Next, consider installing new cables and housing, or lubing your existing
cables, which will allow the derailleur to transmit more tension on the
cable all the way to the shifter instead of wasting it on overcoming static
friction inside the housing. Try lubing your cables first, and then seeing
how it works.

If it doesn't, the next step involves freeing up the derailleur so that the
spring tension of the derailleur can work its best at tensioning the cables.
Spray WD-40/GT-85 into the pivot points of the derailleur, where the two
plates of the parallelogram connect to the knuckles. Shift into the hardest
gear, and then, with your hands off the shifters, manually push the
derailleur all the way across the cog range while pedaling. Alternatively,
you can take the rear wheel out and just actuate the derailleur manually
without having to endure all the noise and wear of actually shifting. If
you use this alternate method, unscrew the limit screws so that you're
actuating the derailleur past its required high limit. This ensures that
when the wheel is actually in the dropouts, the derailleur will make it all
the way out to the smallest cog without corrosion/dirt/sand/crud resistance.
Along the same lines, make sure that you pull on the derailleur outwards,
too (the same direction the spring pulls it). Actuate the derailleur 20,
30, 100 times until it begins to move freely, or at least more freely.
Flush the pivots regularly. Put the wheel back in if you took it out. Test
ride. Report back here... we're interested to know.

--
Phil, Squid-in-Training

Thanks for the detailed response. I had already done most of what you
suggest prior to my post, but it's good to see that I covered
everything.

Shifters are presently partially disassembled with the main "cluster"
of innards soaking in a dish of WD-40....

Report to follow.

Greg