I have a 2017 25 HP carburetor (non-efi) tiller outboard [BATJ 1500835]. Since day one this engine has been extremely cold natured and difficult to start. I have recently changed spark plugs, taken apart and cleaned the carburetors (including new components), and replaced the bystarter valve. When cold starting it takes anywhere from 20-30 starts to get it running. I've searched high and low and can't seen to figure this out. With the bystarter valve, you should be able to hit the throttle three times before starting, turn the key and get to running in one or two tries.
Once it finally starts and warms up, it runs great.
I am running clean non-ethanol fuel....