Thinking about using homemade rings for alfine and nexus hubs.
1. Is it worth using these rings for other than Rohloff hubs?
I wouldn't bother. Never had any problems with Shimano Nexus hub flanges.
To me the most probable failure modes of the 7 and 8 speed Shimano hubs seem to be:
- water getting in through the large right-hand bearing. This was a problem with older versions, newer versions have better seals. Two solutions for this (i) regular regreasing. I use a"waterproof" grease designed for use on outboard motors. (ii) fitting an oil port and using synthetic oil instead of grease. This mimics the old Sturmey Archer hubs, where the slow leaking of oil outwards tends to stop water entry.
- internal damage due to bad adjustment (check this regularly) or a worn cable sticking (inspect and replace as soon as it seems a bit sticky).
The first version of the 11 speed Alfine was reported to have a lot of internal failures, which put me off trying it. Probably corrected in later versions. But cable adjustment still seems to be more critical than on the 7/8 speeds.
If you crack a flange on any other hub it's game over, there's no market for re-shelling a Shimano when you consider the price of a complete replacement.
Except if you run several, in which case cannibalisation is possible. A few years ago the Nexus 8 Premium hubs were available on offer at about £60, at that price it isn't worth trying to source the hard to find and relatively expensive spares for Shimano gear hubs. I bought several hubs, including two I intended to cannibalise for spares. As I have not yet needed to do that, one has since been fitted to a bike.
