Long-Term Oil Port Performance - 15 Years

Background

My first Shimano hub gear only lasted two years before failing catastrophically, in October 2008. Dismantling it after failure it was evident that it had let water inside and there was lots of corrosion. It's not a pretty sight, but the full detail (and nasty pictures) is listed on another page.

Modifications

Recalling that good old Sturmey-Archer hub gears work forever, withstanding any abuse as long as they get an occasional dose of oil through the hole in the shell, I decided to see if I can put an oil port on my new hub.

Longer Term Performance

When the hub was nearly two years old (almost the age when the first hub expired), and had had a year unmodified and a year with an oil port, I opened it up to see how it was doing. That is reported on the one-year-later page.

At about eight years and 20,000 miles, I opened it up again. That is reported on the eight-years-later page.

Now the hub is a little over 15 years old, and has covered something like 31,000 miles it has been making some very unpleasant (grinding) noises, and is quite finnicky about the shifter cable adjustment. This seems like another good time to have look inside...

Left side cup, cone cone and bearings looked good.

Unfortunately, the same cannot be said of the rest of the internals. They are exhibiting the sticky muddy gloop reminiscent of the first catastropic failed hub.

(The apparently missing balls have just dropped out and are in the muddy blobs at bottom left.)

Though it looked horrible at first, the internals mostly cleaned up OK. Visually most of it it looks as good as it did after eight years, but ...

... the right side cup and cone are both horrible.

The balls from this side are all present, though not in good condition.

Roller clutch tracks inside the hub shell and left side cup are OK to good.

In case you're interested, this is a 21T steel sprocket after about 36,600 miles (nearly 1.5x the equator), with a new replcement for comparison. I don't know how many chains it has been through.

Conclusions

I re-greased and re-assembled and actually it still runs tolerably - grumbling noises when you free-wheel the wheel in the maintenance stand, but riding in traffic it's not actually audible over all the surrounding noise. I worry that the cup/cone/balls are grinding down though and it's going to shed balls into the innards (like the first hub did) when it grinds out enough tolerance.

It's good that the hub is still functional after 15 years and 31,000 miles of year-round all-weather use. It's at the end of its life, though, solely because of that right side ball-race. The cone is part of a spare that exists, but the cup is pressed into the hub, and not replaceable. It's a shame Shimano can't solve the right side sealing. If that race lasted longer I think the hub has quite a bit more life (with suitable finessing of the shifter cable adjustment).

At eight years I said "I have my doubts that this hub is going to last another eight years, however..." and I think actually it would limp on that long. However, I'm going to replace it. The nearest match is now a SG-C6011-8R, but I can't find one (in the UK - there are Euro suppliers with stock but they won't ship to the UK - thanks Brexit) so I'm swapping to a new SG-C6001-8R, which is nominally identical spec except that it's 'Driving efficiency: Standard' where the SG-8R36 (this hub) and the SG-C6011 are 'High'.