On general principle I would agree except for the fact that my pressure regulator is supposed to be factory set at 59.5psi and it idles at 72psi on the feed side. Could be its not because of the smaller return but it's been suggested that is the reason. IThe return only runs about 3-5psi back to the tank so I'm not sure why it might have that effect other than it leaves the throttle body through a 3/8" line and is necked down to 5/16" steel down at the frame. I'm no expert, I just listen to what they say.
With only 3-5psi on the return that's not the problem. Either your gage is not reading correctly, or the regulator was not set correctly, or it was damaged and there's too much pre-load on the regulator diaphragm spring.
For example, installation of the regulator by pressing on the top of it can deform the body enough to increase pressure. Although being almost a perfect 1bar (manufacturers use metric units), it's more likely it was set on the production line to the wrong specification.
Or, one more thing to check, is your tool measuring in “gauge†pressure or “absolute?†That would also account for a 1 bar delta.
