The shifter mechanism at the hub should not be lubricated. Dry, dry, dry. Oils, greases, whatever will attract dirt/contaminants. We can start with that. Once that is cleaned and returned to proper condition, if a problem remains we can move on to other things like cheap galvanized cables swelling up in the cable housing or pinched housing or cable fray at the handlebar end.
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I shouldn't have to "make myself more visible;" Drivers should just stop running people over.
Car dependency is a tax.