History of Yamaha engines

[stul]

Hi
Looking for history of Yamaha engines namely 40 hp, can anyone tell me if the auto lube around mid 1980s was introduced along side the 3cylinder pre mix, was it a new development or just an option. Did it totally replace the pre mix, which is the better buy?
Thanks Stuart

[walruz]

Can't answer all your questions but autolube vs premix:

Autolube will usually use a LOT less oil than premixing.

I have a 91 2 st autolube and I use less oil than I did with my previous 60 that was premix.

Ian