My old Mity at one point had too short wires, so I lengthened them simply by soldering onto the terminals of the bar mount, and then I stuck silicone sealant in there. Worked perfectly for a long time. The silicone eventually started to come loose from the bar mount as a little block, though, rather than staying put.
Speaking of HV, I can't imagine the voltages in the Cateye causing any significant electrical stress, and hence any voltage induced failures even without Goop or some sealant, as long as everything started clean and stayed clean. I could imagine an additional mechanical problem having lead to another open circuit due to the three miles of road vibration. In some such repairs I've tried, I've not been able to re-solder broken leads/pins with low enough energy to prevent additional damage. Two reasons for this: too cheap to buy the proper very-low power soldering system, and not proper skills for such delicate work. And this after having been certified to solder according to NASA standards! But nothing in spacecraft back in those days was as tiny as modern commercial electronics.
Datakoll, I think something else in your Cateye has broken, and it might or might not be associated with your repair, based on what you've told us.
By one of those odd coincidences, Dan Rowan was probably the most famous kid to come out of the McClelland orphanage down the street from where I live.
Rowan was the one with the moustache and a fistful of medals as a fighter pilot.
It's still wire. It's long and it conducts electricity, that's close enoough for government work. Who cares if it's not technically made out of metals.
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