This is something I'm curious about. When adjusting the valve lash I removed a small oil pipe to allow better access to the adjusters. Here:
The service manual refers to this as an "oil pipe" yet when I removed it it had regular crush washers but
no banjo bolts. What the...? Ok then, oil must pass into the pipe past the bolt. Granted, it doesn't need to get past the threads, but look at how much clearance there is for the oil to move through:
This bikes previous owners performed some pretty stupid maintenance, did someone get mixed up and put the wrongs bolts here? Or, is this the way it is on your bike too. Just curious.