Why would you bring spare cartridge bearings? It's not like they fail catastrophically, and unless you're riding 100k a day for months on end they won't wear out enough for you to notice.
Trip might last 2 months, might last 12. DI don't have a time limit. Just tuck them away and forget about it.
@Stoo61 started
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Why would you bring spare cartridge bearings? It's not like they fail catastrophically, and unless you're riding 100k a day for months on end they won't wear out enough for you to notice.