exhaust sludge

the clip was on one so so i put it at the second one down i've leaned out
my main from a 390 to 340 one step down at a time it seemed best at 340 but
it was surging pretty bad i've done nothing else

 

So tells us what your spark plug insulator looks like when you do a
"plug chop". Run the engine at full throttle for a mile or so, pull the
clutch in as you hit the kill button, coast to a stop without idling,
let the engine cool off so you can pull the spark plug and see what it
looks like.

Also, are you over-oiling the air filter? Is there a dead rat in the
air box, or something restricting airflow to the carb? One guy said he
had a rodent's nest in the airbox, another guy said he found shop
towels in there. I personally had a home made air cleaner hose collapse
on me, and that acted like a choke.

Then there is that possibility of a bad petal on the reed block
allowing the carb to suck a double shot of fuel...

 

no and no