- Sep 28, 2016
I'm a little bit puzzled with the tune on my bike. Running extremely rich at 50-100% throttle. Should be a main jet concern I assume. Idles fine with a stock pilot jet and air screw at stock position. It's a freshly rebuilt bottom and supposedly has about three hours on it. Fresh plug, pro circuit pipe and moose filter. I figured with a stock 172 main jet it would run lean with the mods. It currently has a 160 and is still running extremely rich. Also running 40:1 on my fuel mix. I haven't messed with the jetting yet but wondering if I should be looking for anything else before I start.