I posted this under the YS Support forum but I'm affraid it might take to long. So I am posting it here in hopes that someone might know.

I have a YS 120NC that runs extremely rich on the low end. I ran it last year but I had to really crank in the regulator in order to get it to idle. I thought I read somewhere that you could drill out the hole in the throttle body a little larger and it cleared up the rich low end. Is this true? If so how big do you enlarge the hole to? Would a 1/16th be in the ball park?