A pint per tank would do the job
Snowbum talks of just this and says you only need a small amount of lead to achieve any needed benefit with valve seat recession.
I don't have much to report on the bike but after 1.5 tanks through the truck the pinging is significantly reduced or maybe even gone!
I was cautious about claiming any effect but it really does seem to reduce pinging. Still not sure how it manages this as it's not an octane booster in the conventional sense. I'm short of miles on the bike too and it's the wrong time of year to be looking for improvements in fuel consumption.
I am glad to have a little oil in there though during the storage period as I'm not intending to drain the tank this year.
I did empty the bowls today as the bike has been stood for 3 weeks with maybe 3 more weeks to come depending on when the roads dry out. Surprisingly in that short time getting on for half the fuel in the bowl had already evaporated. Easy to see how carbs can get gummed up in storage.