KDXRIDER.NET

Do you guys think a 42 pilot 155 main needle set at 3rd notch from the top is too lean to break in a new sleeve? Most of my riding is at about 1500 ft with 40:1 mix. The bike ran pretty well with this setup before the rebuild, maybe even a little rich.

If it's good enough to run perfect or a little on the rich side, it's good enough to break-in ;) I generally use a small amount of non-synthetic (saw oil, pure castor) for break-in, but that's debatable. Small amount as in 1gal of gas, not any ratio.

The piston was really loose when I tore it down so I'm not sure how accurate that jetting was. I was thinking maybe I should run the first 5 gallons of gas at 32:1 to be on the safe side and keep an eye on the plug.
The paper I got with the jug when I got it back said run way richer jets ( 155 for example run 165) same with the pilot and the needle at the richest setting but that almost seems like overkill and asking for fouled plugs.

Run it as you normally would. No need to alter jetting or ratio.