I use oil for mig welding wire. It is formulated to not do anything detrimental to the liner . Comes in a small can that is not pressurized so you have to dribble it in but it works well. It is conductive so on a carbed bike if much goes down the cable it may short out the spark plug if some goes down the intake. Guess how I learned that! Look in the welding supply section. While you’re there pick up a couple mig tips that you can use for fittings on the intake manifold. Miller welders for one uses them.
