That's great!
And at 50 :1 there is no way I'd be reducing the oil in the mix.
The 4 stroke takes a feed from the top of the cylinder head, or somewhere, so oil gets into that fuel too.



.
I disconnected the pipe from the air inlet but it made no difference.
I think the age of your machines may be a factor, my oldest, the wheeled jobby, is the oldest, apart from the 4 stroke strimmer/brushcutter and seems to be the strongest. An Olio-mac Italian number.
So BIG question. How do YOU store them??????
(And in a little aside there was a Merkin on tother thread who reckoned it was easier to store engines up norff in Merka than darn saff?!)