I have a Yamaha 8 hp motor I have not used in 2 years.i started it today. It will only run with the choke pulled out. I remember the last few times i used it it wouldnt run at idle speed. Any ideas what is wrong? My knowledge of mototrd is not very good.

Gummed up carb from gas being left in it.
Remove carb and clean with real carb cleaner, not the spray stuff, but something like "Berryman Chem-dip".
In the future leave the motor with non-ethanol, stabilized gas in the engine in the off season.

Some of the real carb cleaner is not plastic friendly,,,,,, read labeled instructions

Run some Yamaha ring free through it first.

got that right Vinke, good advise

Premium fuel does not have as much phenols as does the lower grades of gasoline which is the killer to rubber seals. It is actually not the Ethanol content which is bad

That is what I was thinking something with the carb.

Strip the carb down completely and put the parts in a ultra sonic bath for half and hour. Reassemble and you'll be good to go. I have a couple of customer engines sitting here as I type that have the same problem. When working for a customer, I like to use new gaskets when I put the thing back together. On my own stuff I don't usually bother with them if I can get away with it. If you are careful when you strip it down, you should be able to use the gaskets it has in it now.

^^^^
Scuba 1
When you put parts in an ultrasonic bath what type of cleaner/solvent do you use?