Replacing the Wind Cups
It is easy to replace the wind cups if needed. The cups have a tiny magnet in the flange at the base for the wind speed sensor. Earlier models had a brass jewel bearing in the top, but miniature ball bearings are now used in the Wind Instrument RB™.
For removing the wind cups, do not remove or twist the nose cone, which is permanently attached. Just loosen  the black dome nut and  the brass set screw in the side of the black axle tube. Use a 2 mm (or 5/64″) Allen key for the brass set screw.
The nylon dome nut can be loosened with a 3/8″ box-end wrench. Remember to turn counter-clock wise to loosen, to avoid stripping the threads on the nut. The replacement is quick and simple, but if you do the repair yourself, SailTimer Inc. is not responsible for any damage that is caused.
The axle-wind cups assembly is a single unit that is press-fit into the black base. To remove the previous axle under the wind cups, just pull it out (with pliers if needed, possibly wrapped in cardboard or rubber if you want to protect it). Then put a drop of superglue on the base of the new axle (or quick-cure 2-part epoxy if the fit is loose), and press-fit it into the socket. Then check that the cups spin free before reassembling.
The new assembly does not use the C-shaped retaining clip above the flange on the base of the cups. If your model has that, it can simply be left in place.
During reassembly, put some adhesive (e.g. a small drop of Marine Goop or superglue) on the threads under the dome nut to make sure that nothing comes unscrewed.
Then tighten the brass set screw, and you’re done. It seats firmly without needing any adhesive.
This will be clearer once you take it apart; don’t worry, it is pretty easy. You just remove the dome nut and loosen the set screw, then pull the tail back, to get the cups off.