How many turns is your mix screw out? It seems 2.5 is too much.

[DreamV4]

??????????
I'll check spark plugs tomorrow.

 

[user 16790]

mine are set at 2 3/4

 

[one2dmax]

Anywhere from 1-4 is in the "range". They are set with an EGT probe from the factory and each cylinder is set independently (so not all the same amount of turns). You can usually use around 2.5 turns as a good starting point.

 

[Zu1]

Try at 2. And do cold start in the morning. If engine hesitate getting rpm, open a bit. If it seems solid, then you may tight it further 1/8. Do not lean it unnecessary.
Richer 10,000 miles are less damaging rather 10,000 miles of too lean.

Plus let it warm up well, if you want it bit on leaner side.
I have set it on 2.5 though. and mine seems ok with that. in colder days, i keep it on 2.75 usually for easy start and idling.

 

[DreamV4]

Try at 2. And do cold start in the morning. If engine hesitate getting rpm, open a bit. If it seems solid, then you may tight it further 1/8. Do not lean it unnecessary.
Richer 10,000 miles are less damaging rather 10,000 miles of too lean.

Plus let it warm up well, if you want it bit on leaner side.
I have set it on 2.5 though. and mine seems ok with that. in colder days, i keep it on 2.75 usually for easy start and idling.

2 feel better. And engine didn't stall. I also increased idle.