I have recently found a puddle of oil on the drivers side engine shelf, nothing on the passenger side. This is the second time I have found this. The first happened after a long drive, this time was after a 30 min ride. The only change has been a valve adjustment. But I don't understand how a valve adjustment would cause oil to pool on top of the shelf. Any ideas?

I'd check the valve cover gasket.

Does your heads have the oil breather tubes coming out next to the air intake tubes? Most D-Jet heads had them, not sure yours do (i only see that you have a 2056)

If so, one of them might be leaking blowby and oil on that one side.

I hope this helps.

Valve cover gasket, head breather connection or hose, thermostat wheel through bolt.

Those are 3 things i can think of that are in that area.

I'll check all of those things. I thought it might be the valve cover gasket, but how does it get to the top of the engine shelf? Thanks guys, I appreciate the advice.

when we used to blow valve cover gaskets on the old race car
it was always oil on the top of the shelf

I think it goes below too... but drips away
the oil on top was always the indicator.