need some help on base timing on a 2003 mercury 125 2+2 outboard

[dog22]

I have a 2003 mercury 125 2+2 outboard does anyone knows what the idle base timing should be on this motor

 

[racerone]

Maximum timing advance is most important.-----Timing where throttle plates open is important.-----Where the timing is at smooth idle does NOT matter !-----This motor only runs on top 2 cylinders.----Bottom 2 carburetors kick in at around 1800 RPM.

 

[Dave1027]

Base timing is supposed to be set to make the engine idle at about 650 rpm. So base timing is not set to a timing spec. It's set to an rpm. Max timing is set to a timing spec. On mine (I have an older model) I believe it's 25 BTDC.