I've built a 421cc engine, non power valve, 21cc domes, 35PWK's, CPI pipes. I'm at 3200 ft. temp's 50-90 degrees.
Jetting is killing me. The engine idles great, pulls strong on top, but if your looking for anything off idle to 3/4 throttle
is bogs, spits, sputters until it cleans out. I started with 53 pilot, 160 main. Very rich. I'm now at 35 pilot, 145main, and
every where in between, much better. Plug is slightly tan, heat range looks good.
Help from anyone would be greatly appreicated.