What is normal oil pressure?

Hi Fellas,
I want to check the oil pressure on both my 82 550 LTD and 80 750 LTD 4 cylinder. What kind of oil pressure is acceptable? This would also be helpful because I don't want a gauge that goes from 0-150 psi when I'm might be need in the 0-10 range (fictitious numbers)

Thanks

Because that bike has plain bearings in the crank shaft, just like the 650 and 750, it will have relatively high pressure. Unlike the KZ900/1000/1100 which has needle bearings and has pressure at about 3-4Psi. Your factory service manual should list your pressure. I suspect it will be between 25-45Psi.

There are two tests in the FSM. One for the relief valve, and one for oil pressure.

Relief valve:
Test with engine at room temperature. Check at various RPMs. The pressure should max out in the range from 63 psi to 85 psi. If it's higher than 85, the valve is stuck closed. If lower than 63 at RPMs above 5000, the valve may be stuck open.

Pressure:
Test with the engine at full operating temp. (194 degF).
At 4000 RPM, it should be 28 to 36 psi.

The pressure test point is the big bolt/plug below the ignition cover, on the right side of the motor.

Sorry Lou, shoulda read this post before PM'ing...

Thanks guys. I think it would be cool looking to mount an oil gauge for fulltime use. Can I use this port full time and get a mountable gauge, or would this be a bad idea? Maybe the oil would get stagnant/dirty in the dead leg between the motor and gauge? Or maybe I would be introducing another path for a leak to find?

Like I said in the PM, I would try to get an electric one, instead of the ones with the hose going to the gauge. Although, I'm not sure if the electric ones are more accurate or not.

Also, the FSM shows the hookup under the ignition cover for testing, but I don't know why you couldn't use the original oil-pressure-switch port instead. Maybe do a test on the right side port to confirm it's ok, then hook up to the underside port for the permanent installation.

What about this one? Relatively cheap, eletric... not sure what it looks like mounted though.

www.autozone.com/autozone/accessories/Su...23_0_0_&sortType=low

apbling wrote:

Sorry Lou, shoulda read this post before PM'ing...

Thanks guys. I think it would be cool looking to mount an oil gauge for fulltime use. Can I use this port full time and get a mountable gauge, or would this be a bad idea?

The gauge I had on my 750 mounted at the hole the oil sending unit goes into and then the sender screwed into the top of the fitting.

As for pressure: I think the overpressure "pop off" valve will open at somewhere around 65 - 70 psi which could happen with a cold engine. In the case of an "experienced" engine, you can probably see HOT oil pressure in the ballpark of 40 - 45 psi at maybe 2000 - 3000 rpm or above. At idle (very hot) it might drop to 15 - 20 psi.