plug chop

If the engine is bogging off when you hit the throttle, it's not too lean to do a plug chop.

If the engine is cracking up (popping, sputtering stuttering or however you prefer to say it) at WOT you're way to rich.

Once you get the jetting halfass close, THEN you do plug chops.
 
I have not plug chopped until my heat cycles are complete and i ran a tank of mix through. I choose to do 6 heat cycles, but you can do as many as you like. Everyone does it different-As stated just get it in the ball park (guess-ti-mate) then when your done with heat cycles ride easy on the first tank, then do your WOT plug chop. The others 1/4 , 1/2 chops can be done after heat cycles if you choose to do those.
 
i had it out last week end and it didnt sputter or anything.although as i was driving down the road i looked back and didnt really see a smoke trail.put i quickly but my hand over the silencer and i seen smoke so i hope it isnt too lean.it fires up like a charm and idles perfect.doesnt bog at all but i havnt really pushed to to the max yet
so the NGK BR8ES is a good plug?
not too hot?
 
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If it's running "ok" you're in the range necessary to get it to do a plug chop. It can be in a really wide band of rich to lean and run "ok". I had a 148 main in mine when I left for busco beach and it was running "ok" around the yard.

Once I got there and did my plug chops I ended up at 158 and that was perfect for my engine.
 
You'll still need to do some plug chops to make SURE you're right but I would figure a 310 main jet will get you right where you need to be.

I know a lot of people curse vito's products BUT they make a decent carburetor jet kit. They include jets from 290 to 340 which should cover you up one side and down the other... and a new needle all for like $25.