Let’s see, I’ve either owned or had on loan five bikes with Shimano Alfine 8 hubs, four with Shimano Nexus 8 hubs, two with Sturmey Archer 5 hubs, three with Sturmey Archer 3 hubs, one with a Nexus 7 hub, one with a Nexus 3 hub, and one with an SRAM iMotion 9 hub. Among all of those internal gear hubs, I’ve never had an issue until the most recent Alfine 8 on my Civia Bryant.
It’s not unusual for internal gear hubs to make some noise when they’re new, but they almost always quiet down after a brief break-in period. This particular Alfine 8 started out noisier than most, and it’s only gotten louder over time, to a point where it was obvious something was not quite right. I finally consulted an expert on internal gear hubs who recommended I have it serviced. Being the sucker-for-a-good-bike-maintenance-project that I am, I decided to take it on myself.
The recommended process involved removing the internal parts of the hub (they come out in one piece), briefly soaking them in Shimano’s special IGH oil, then reassembling everything (while I had it open, I also added some grease to the bearing races and around the seals). The specific steps included removing the cassette joint, sprocket, and dust cap on the drive side, then removing the disc caliper and bearing cone on the non-drive side. Once the external parts were removed, the innards of the hub slid out toward the drive side in one piece. Once the internal parts were free from the hub body, it was simply a matter of dunking the whole thing in Shimano’s oil bath as per their instructions, then reassembling.
I’m happy to report the service worked. The snapping/clunking sounds I was hearing while pedaling lightly are now gone. It’s my understanding that the purpose of the oil is not so much to act as a lubricant as it is to refresh the grease within the internal parts of the hub. It appears either the hub was not lubricated sufficiently from the factory or it sat dormant long enough that the grease had started to dry out (my bike is a NOS 2009/2010 model). Whatever the case, everything is smooth and quiet now and I should be good to go for at least another couple of years.
This was the first time I’ve opened up an IGH. The process was less daunting than anticipated, though I wouldn’t recommend it for anyone other than the experienced home mechanic who enjoys a challenge and is willing to do his/her homework. For those who don’t have the experience to undertake such a process, dealers who regularly service IG hubs should be able to do a service like this in under an hour (assuming no other issues). Of course, if there is actual damage to the hub, the time it takes to do the repair may be significantly longer with correspondingly higher costs.