I use the old one whith the K/B marks on it , and it's a 7,75 mm hole in it. That should be 0,305 i think in us. That sucker should fit better on a 21 engine !!
Does anyone know where to find a better carberator to my K&B 7.5 ? I have heard of red , gold and black carberator . Who is best and where to buy them ?