Shimano hub gears

Regulars (if there are any regulars left who actually ride bicycles
rather than are here just to attack cyclists) may recall that I had a
Shimano 8 speed hub gear that expired horribly a little over a year
ago.

Inspired (or maybe shamed) by email correspondence with someone who
asked how my oil-port modification had performed, and since I was
fitting a new tyre this weekend so had the wheel off the bike anyway,
I have:

1: looked inside to see how the new hub has done after a little over a
year (but most of two winters)
http://www.astounding.org.uk/ian/hubgear/index.html

and 2: actually done the oil port modification to the new hub
http://www.astounding.org.uk/ian/hubgear/oilport.html .

The truly horrible first-hub-innards (for those with either a strong
constitution or no sense of mechanical empathy only) are still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

I've also added some how-to-do-it notes about getting into the hub to
the main page.

regards, Ian SMith
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Ian Smith wrote:
Regulars (if there are any regulars left who actually ride bicycles
rather than are here just to attack cyclists) may recall that I had a
Shimano 8 speed hub gear that expired horribly a little over a year
ago.

Inspired (or maybe shamed) by email correspondence with someone who
asked how my oil-port modification had performed, and since I was
fitting a new tyre this weekend so had the wheel off the bike anyway,
I have:

1: looked inside to see how the new hub has done after a little over a
year (but most of two winters)
http://www.astounding.org.uk/ian/hubgear/index.html

and 2: actually done the oil port modification to the new hub
http://www.astounding.org.uk/ian/hubgear/oilport.html .

The truly horrible first-hub-innards (for those with either a strong
constitution or no sense of mechanical empathy only) are still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

I've also added some how-to-do-it notes about getting into the hub to
the main page.

regards, Ian SMith

My SA 5-speed so far seems to be coping ok with the weather, but I'll
get it serviced later in the year to be sure. I'll be after an 8-speed
for my next bike so I'm heartened to read the new Nexus is looking good.

I'll be interested to read in a few years time how your oil port mod has
fared, although I doubt I'd ever have the nerve or nous to try it myself!

--
www.slowbicyclemovement.org - enjoy the ride

Ian Smith wrote:
Regulars (if there are any regulars left who actually ride bicycles
rather than are here just to attack cyclists) may recall that I had a
Shimano 8 speed hub gear that expired horribly a little over a year
ago.

Inspired (or maybe shamed) by email correspondence with someone who
asked how my oil-port modification had performed, and since I was
fitting a new tyre this weekend so had the wheel off the bike anyway,
I have:

1: looked inside to see how the new hub has done after a little over a
year (but most of two winters)
http://www.astounding.org.uk/ian/hubgear/index.html

and 2: actually done the oil port modification to the new hub
http://www.astounding.org.uk/ian/hubgear/oilport.html .

The truly horrible first-hub-innards (for those with either a strong
constitution or no sense of mechanical empathy only) are still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

I've also added some how-to-do-it notes about getting into the hub to
the main page.

regards, Ian SMith
I had a 7 speed that did similar milage for 5 years before it gave trouble.
I took it to pieces with no expection of getting it back together.
I recon your problem was with adjustment of ball bearing races.
It might have survived if you'd fixed brearings at first sign of trouble

Jim

On Tue, 19 Jan 2010 15:33:34 +0000, J. Chisholm wrote:
Ian Smith wrote:
Regulars (if there are any regulars left who actually ride bicycles
rather than are here just to attack cyclists) may recall that I had a
Shimano 8 speed hub gear that expired horribly a little over a year
ago.

I had a 7 speed that did similar milage for 5 years before it gave trouble.
I took it to pieces with no expection of getting it back together.
I recon your problem was with adjustment of ball bearing races.
It might have survived if you'd fixed brearings at first sign of trouble

How do you think improperly adjusted races (they weren't improperly
adjusted btw) causes water to get through the seal and trigger
corrosion throughout the internals?

The early 8 speed hubs simply had inadequate seals. The seven speeds
were fine, the later eight speeds seem fine so far. It's well
attested - there are lots of similar accounts.

regards, Ian SMith
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Ian Smith writes:

The truly horrible first-hub-innards (for those with either a strong
constitution or no sense of mechanical empathy only) are still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

Good work. No doubt there was lots of water and rust in there too, but
what you identified as mud might just be the old black Shimano hub
grease. Even new, it looked and felt not dissimilar to silt (very
expensive Japanese silt, obviously). IIRC, it was `obsoleted' at some
point after the original 8-speed hubs were launched, so it's quite
possible that yours had this.

--
Mark

On Wed, 20 Jan 2010 19:23:27 +0000
Mark Williams ] wrote:

Ian Smith writes:

The truly horrible first-hub-innards (for those with either a strong
constitution or no sense of mechanical empathy only) are still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

Good work. No doubt there was lots of water and rust in there too,
but what you identified as mud might just be the old black Shimano hub
grease.

Any grease mixed with a load of rust particles and water tends to look
and feel like mud.

On Wed, 20 Jan 2010, Rob Morley wrote:
On Wed, 20 Jan 2010 19:23:27 +0000
Mark Williams ] wrote:
Ian Smith writes:

The truly horrible first-hub-innards (for those with either a
strong constitution or no sense of mechanical empathy only) are
still at
http://www.astounding.org.uk/ian/hubgear/mangled.html .

Good work. No doubt there was lots of water and rust in there
too, but what you identified as mud might just be the old black
Shimano hub grease.

Any grease mixed with a load of rust particles and water tends to
look and feel like mud.

Indeed, and that's what I think it was - it was pale mud, as would be
generated from rust and white grease. In places, some of the grease
was merely off-white, as can be seen he
http://www.astounding.org.uk/ian/hubgear/DSCN2464.jpg

However, that same picture shows white, brown and grey. It's
possible, I suppose, that the grey is a mix of white and black - would
they have used different greases at different stages of assembly? It
seems a bit pointless, if it's all going to migrate around and end up
grey, but while I can explain the white grease at the middle of the
picture, and the brown grease to the right being white grease + rust,
I'm not sure what gives the grey grease to the left.

Particularly as it was (as noted above) accompanied with lots of water
and corrosion (on balls, cups, cones) that had got as far as pitting
and severely roughening the surface, I'm confident it can't be
entirely attributed to coloured grease. However, I hadn't
contemplated that it might be anything other than normal white grease.
Shimano roller brake grease is black - really nastily messily black.
I'm very glad the hub did not contain much of that (or anything
similar).

The good news after a few days of riding the re-assembled new hub is
that the presence of the nylon screw projecting slightly inside does
not seem to have upset the hub. I didn't think it would (and I didn't
really think I might have accidently left a spanner inside), but it
was worth isolating my changes. I might try putting oil in this
weekend - the most likely way it all goes wrong (I think) is if I put
it in and it comes ****ing straight out through some breather or
inadequate seal. I have certainly read someone's account of trying
the same thing in a new model other brand of hub (but can't remember
if it was SA, or Sachs, or who) and finding the oil all drained out
very quickly.

regards, Ian SMith
--
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Ian Smith writes:

Any grease mixed with a load of rust particles and water tends to
look and feel like mud.

Indeed, and that's what I think it was - it was pale mud, as would be
generated from rust and white grease. In places, some of the grease
was merely off-white, as can be seen he
http://www.astounding.org.uk/ian/hubgear/DSCN2464.jpg

However, that same picture shows white, brown and grey. It's
possible, I suppose, that the grey is a mix of white and black - would
they have used different greases at different stages of assembly?

Pass---this is Shimano we're talking about[1]. You seem to have some
yellow stuff where the left-hand bearing should be on your new hub!

On your old hub, is the part with the white grease the clutch? There is
nothing which looks like that in my 7-speed (where right-hand ring gear
connects directly to the sprocket). If it is not strictly a
transmission part, then it's possible that they have used different
stuff in the factory.

It seems a bit pointless, if it's all going to migrate around and end
up grey,

When all is well, it doesn't seem to migrate around very much. The
pictures of your new hub still show several bits without any grease on
them at all.

but while I can explain the white grease at the middle of the picture,
and the brown grease to the right being white grease + rust, I'm not
sure what gives the grey grease to the left.

If you take some `new old stock' black grease and beat water into it
with a screwdriver for 5--10 minutes, then it ends up dark grey and as
shiny-looking as the grey grease in your picture. With more
persistence, you might get it similarly pale.

[...]
However, I hadn't contemplated that it might be anything other than
normal white grease. Shimano roller brake grease is black - really
nastily messily black.

Yes, but different to the hub gear grease. The brake grease is smooth
and slimy while the black hub grease is grainy and relatively stiff.

[1] Or whoever makes their hubs---at least some of their dynamo hubs are
made by someone else, I think.

--
Mark