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[PeteF]

After lots of discussion about oil pressure on the EFI engines (or lack of it) I decided to find out just what pressure I had.
Upon removing the RHS cover I found the oil pump/ filter housing O ring to be crushed down to about half it's width which would suggest it was making a decent seal but when left for a few hours it did not recover it's shape which suggests it's not particularly good quality.
I replaced it with a viton item which I fixed in place with a dab of grease (I'm not convinced superglue is a good idea)
I then fitted an oil pressure gauge by drilling that blanked-off drilling into the oil filter chamber.
I made up a brass adaptor threaded M8 and tapped the case.
The gauge is a 1/8 BSP thread and I don't intend to leave it there all the time; it's just for checking the oil pressure periodically. I have a blank to cap off the brass adaptor which will be left in place so the thread into the case will not be disturbed every time I check the pressure.
I do understand that the oil pressure will be worryingly low at tickover with a hot engine but as long as I get a decent value at running speeds it will be OK.
I understand these engines don't have very high oil pressure anyway.
At least the figures I got prove that the oil pump is working and the seal is doing it's job.
Of course, the next step is to prove decent oil flow to the top end!
Cold engine - tickover 45psi - 75psi when revved.
Warm engine_ tickover 20psi - 55psi when revved.
I'll try to link the video I took (just on the phone - not brilliant quality)
https://youtu.be/Sjv_0pK_mUk

[Rattlebattle]

I would think those pressures are fine. 20 psi on tickover when warm is very good, I’d say. IMHO with those pressures and assuming no blocked oilways there’s no need to be concerned about the valve gear. Mine was in perfect condition at 6500 miles; Harald was unlucky.

[PeteF]

Thanks RB. i'm coming to the same conclusions. It's nice to be certain anyway.
I'm thinking, now I have the port drilled out, I'll fit an oil pressure switch and have an led lamp on the dash somewhere.

[Cranky]

I have just 5000 km on my 2017 Re ECU EFI, but not EFI no longer .

As I have said somewhere else I converted the temp sensor to a oil pressure warning light using the MIL lamp.

It goes out immediately when cold but is one at idle when it is hot and I mean hot --it is 35 degrees today in bright sunshine.

It flickers at a normal idle but I do tend to set it slow. The oil pressure switch will be 7psi as most car switches are.

Therefore I am envious of your pressures.

[PeteF]

Cranky, I've not tried it HOT yet, that was just warm.

[Cranky]

I will be very interested to hear of your findings when she is hot.

[PeteF]

OK Cranky here's the HOT figures.
After 20 miles of fairly hard riding I got the following.
Oil temp 80C
Oil pressure @ 50 in top - 35 psi (my usual cruising speed)
Oil pressure @ 60 in top - 45 psi
Oil pressure @ 70 in top - 50 psi
Bumbling along at 30 in fourth - 20 psi
At tick-over it barely registered on the gauge but it is a 0-300 instrument and not designed for such low pressures.
The slightest blip of the throttle popped it up to 20 psi.
I think I'm good?

[Cranky]

Thanks for that. Im trying to interpret what that means to me with a 7psi switch at the head. I think its sounds about the same. Thank you.

Mine (7psi) flickers at idle when hot but it will go out as soon as any throttle is applied.

Its not exactly good though is it, probably why they (RE) did'nt put a guage in.

Would seem then that the 500 ECU prefers a good flow and splash about rather than oil pressure.

The reason I wanted to know was that I like a slow idle. In this case of almost zero pressure at idle then a slower idle wont make much difference.

[PeteF]

You have to remember that 3 psi will give a head of about 6ft.
OK, there will be restrictions but just a few psi will get quite sufficient oil to the bearings and top end at tickover when the engine isn't working hard.
Realistically the top end would manage quite alright at tickover for minutes on end with no extra oil being delivered. Just look at the old total loss systems.
I think they don't fit gauges so as not to worry owners.

[Rattlebattle]

What manufacturer does fit an oil pressure gauge? The most we've had for years is an oil warning light that tells you you're engine is wrecked...As I've said before, all the bearings in this engine except the little end (splash fed) and rockers are either ball or needle roller bearings. They need flow, not pressure. The rocker shaft bearings get a positive feed from the pump; this is much better than a dribble from a take-off on the return to the oil tank usually found on Brit singles. IMHO all that is needed is confirmation that the oil pump is working and that oil is not leaking past the o ring seal. If the o ring is leaking, when the engine is started would the oil level in the sight glass not rise rather than fall as might be expected with a sound seal? Certainly on BMW oil heads as soon as the engine is started the oil level visibly and almost instantaneously sinks as the pump distributes it around the engine. It's the same on my Honda. So, is not a simple check just to start the engine on the main stand and see if the oil,level falls or rises, or am I missing something?