Who are you getting to cut the head? It's not bad if you start at 600 and done at 900.at the latest.

I'm wondering how big effect on a jetting have a squish. Most of you guys prefer (if choosed suzuki) NED# needles and I think you are riding on XC/EC models. I riding on GP and for me better working suzuki needles than yamahas, but NECJ. When I put NED# needle I have a problem with bottom and PJ, 42 is too rich and 40 too lean. With NECJ I don't have this problem and the bike is smoother and stronger than yamha needle.

The heads in EC and GP are different I think GP have more compresion, which gives less squish. And the question is, if bike have more compresion (less squish) is he needs leaner gas/air mixture?

I'm on a 300m sea level, depends of temperature change the MJ between 172/175/178. Needle NECJ (#2 or #3 don't remember now) and 42PJ. AS depends of temp. 1,5-2 turns. Spark looks ok in cappucino color.