First, I apologize for the crossposting at mtbr IGH forums, but i figure this topic fits both locations very well.

While in general I like my Alfine 8 IGH very much for touring, there is always a feeling that internals may fail far from the place with necessary tools or a post office. No, it's not common for an IGH to fail completely, but it happened to some people. You know, I have this "what if...." itching.

Well, there is a partial solution to this problem, six bolt cogs that can paired with a centerlock adapter. It will allow to fix the gear and get you to the closest town no matter in what condition your Alfine is.

There are couple of six bolt producers out there, Tomicog in US and Velosolo in UK. The latter looks like it fits CL adapters better. And it does! The one that is 3/32" thick matches a2z adapter really well, no issues at all. There is certainly enough thread to screw the lockring tightly. I've also tried 1/8" thick cog, and it's pretty hard to mount on the CL adapter.

Some photos.
The cog is nicely made and looks good. Weights about 40 gr.




Mounted:




I'm quite happy with the chainline, not bad at all:

Same thing can be done with a 4 bolt chainring , in place of the brake disc, on Rohloff hubs .

In fact they are occasionally used as a center mounted gear box
and running the final drive down to the left side chainstay..