Idle
I have noticed on a 618 at idle(2300) there is a slight shudder I've varied the rpm slightly to 2500 and it's almost completely gone coolant temp at 150 thru out these test
the set up has a 3 blade warp drive 2.6 to 1 belt reduction 2200 is really shaky I have applied just a slight bit of enricher it get worse
my thought is drop the idle jet one size but the rpm at 2300 might be to high on the needle to be effective
thoughts