DragBikeMike has convinced me to change to a smaller orifice and get a bit more oil pressure.

The current orifice was made with a #56 drill that has a diameter of 0.045" and is roughly equivalent to a #120 main jet.

I made another orifice using a #57 drill that has a diameter of 0.043" and is a bit smaller than a #115 main jet (but bigger than a #115 jet).

While a change in diameter of 0.002" doesn't sound like much - the area change is noticeable.  A 0.045" diameter hole has an area of 0.0016 square inches.  The 0.043" diameter hole has an area of 0.0015"square inches.....the change is a 9% reduction in area.

I will make another test ride and see what affect the smaller jet has.  The next size drill I have is 0.042" in diameter - which is likely another 10% reduction in area.

Using very tiny drills on a lathe with a 12" swing is a bit intimidating...it would be so easy to snap the drill if I put too much load on it.  I used a high turning speed, lots of oil, made very slow advances and backed the drill out repeatedly to get more oil in the tiny hole.