I just wiped down the chain with a cloth and lube with a 4 drops of 90w gear oil each link every 500kms. Since it's been cleaned so frequently and not dripping with oil, it doesn't get dirty enough for kerosene.
I use the trip B counter to know when I'm over the 500km. Usually around 800 it gets very noisy and harder to manoeuvre it by hand.
If chain has sand or dirt I use the Honda chain cleaner, otherwise just put more Honda chain lube on every roller on the inside of the chain( on the bottom part of chain lube the roller from the top). You don't need much lube, specially if you put it on the inside, with the centrifugal force it will spread it around.
Afterwards rotate the wheel couple of times with a paper towel resting against the outside of the chain to remove some of the old lube.
Love the feeling of pushing by hand a newly chained bike and the silence when coasting
For day-to-day riding, I usually do it every 3 fuel fills or so. That's right around the 5-600 mile internal that most manuals state. For long road trips, I'll do it every night.