Today I put together a fuel pressure gauge and flow-volume testing setup to create a baseline for my R1150RT. The spec for the pressure regulator is 43 psi and the fuel pump is rated for 110 liters per hour.
Here's a photo of the fuel pressure gauge connected to two QDs salvaged from a plastic to metal QD conversion. And a female QD connected to a collection hose. The idea is to connect the fuel gauge to the high pressure feed hose, and connect the collection hose to the regulator side of the return line so that fuel bypassing the fuel pressure regulator is collected in the container and weighed. This way you can measure both the fuel pressure and total fuel volume.
In order to develop 95 HP (R1150 Max.), the system has to be able to output a minimum of 35 to 40 liters per hour.
Here is the system connected to the motorcycle.
Here is the idle fuel pressure, 44 psi.
I ran the motorcycle for 60 seconds and collected 3 lbs. 13 oz. of fuel which equates to 0.64 gallons (6 lbs. per gallon), which translates to 145 liters per hour. Much better than the pump spec of 110 l/h and easily 3 times the amount required to produce full power. Every 10 minutes the pump runs 5 gallons of fuel through the system.
Thinking back on the failure of my system and the multiple cracks in the hose. I suspect that my system was running fine with some leaks but then one opened to the point where there was little to no fuel pressure. If I'd been measuring pressure and volume once a year I might have caught this long ago.
The 145 l/h will serve as a baseline for future measurement to assess the health of the fuel delivery system including pump, filter and internal hose condition.
As a side note, the new pump is noticeably quieter than the old one. Also the engine is noticeably smoother (am I imagining this?) Which I believe is due to the better injector matching (< 2%) after cleaning.