Trident mystery noise sorted?

Some weeks ago I posted about a strange whining/shrieking noise emanating
from the front of my Trident at speeds around 80mph or so and after some
miles had been covered. The consensus of opinion seemed to be that it was
likely coming from the speedometer drive on the front wheel (definitely not
engine-related because the noise continued after shutting the throttle,
declutching and allowing the bike to coast, and the noise stopped when the
speed dropped below about 60). I haven't used the bike for several weeks
because its MOT had expired (passed OK this weekend but with an advisory
about a slight weep on a fork seal), so today was the first opportunity to
try it out again, having squirted some spray grease into the speedo drive.
Today on the ride to work the noise did not appear. Probably too early to
say that it's sorted, but the signs seem good.