Oil Pressure Light

Hi everyone
this is my first help post that I open in Grisoghetto. It's about a super well-known topic and I hope I'm not boring.
I rolled my 2011 Norge a year ago with the famous A kit.
From that point of view everything works regularly and I always use Bardhal 10W60 oil and I travel 17km/l and linear behavior.
Last year I had a problem with the oil pressure sensor. At high altitude and with a very hot engine, the steady oil warning light came on.
Panic but I returned home only to discover that it was the pressure sensor that had broken, leaking oil from the connector.
After the replacement I had no more problems for a few thousand km.
Then again a ride at high altitude, engine hot and the light comes on with the engine at idle as soon as I go back downhill, just cool the engine a little and I see that the light stays on up to 3000 rpm then to 2500 and so on little by little that the engine cools down.
There is a clear direct link between the temperature and the pressure read by the sensor.
I checked the sensor again at home and it was ok.
Then I go on to replace the famous sump spacer gasket which was in perfect condition but I change it anyway.
Test drive with engine under load and warning light on again at idle with hot engine. When I say engine hot I mean above 125°C
I am quite certain of this because I have mounted my instrument which continuously communicates with the ECU by reading the temperature and I see that I normally always travel above 122° C and
it is easy to exceed 125° C which is the maximum measurable by the control unit.
I also confirmed the measurement with a second temperature probe and the head is almost 10°C warmer than the sump.
However I changed the sensor again, usual test route and again the light was on at idle.
So I changed the oil from Bardhal e UFI filter to ENI and Hiflo filter, still 10w60 but the result is the same, the warning light is still on at idle with the engine hot but I expected it.
I reassembled the sensor and saw a micro oil leak inside the sensor.
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So I replaced it for the third time with the single pin connector version and as soon as I can I will try the usual test route again.
But now I ask you (if there is still anyone who has endured reading this far).
Is it normal for the 1200 8V engine to run at such high temperatures?
I was left to check the oil pressure regulator and the pump gear, but on the Norge 8V this is integrated into the pump and the gear should be metal.
Has anyone had it broken?

Thank you

Vroom, Pete also mentioned the possibility of the oil pressure sensor.
My bike once turned the oil light on out of nothing. The oil level was OK.
It turned out the sensor got cooked by the engine heat.
At the time the dealer installed a new sensor with an isolating extension to avoid direct contact with the engine. This was years ago and it has been working OK since then.

Unless the oil level has dropped below the level of the pick-up it will have little effect on the pressure.

There are a variety of things that can cause pressure and delivery volume loss. These should be considered only after the switch has been disqualified as the cause of the problem as the switches are notoriously sketchy.

The thing is if it isn’t the switch and the light is coming on and staying on then the pressure must be very low as the switch itself operates at some piffling pressure, a couple of PSI or so. That means that if the light is constantly on there must be a delivery problem.

The most obvious common issue is the blown out spacer gasket. This allows internal leakage back to the sump and a diminution in both pressure and volume. Usually though when it gets bad enough to cause the light to illuminate the delivery is so poor that the cam chain tensioner plungers get insufficient oil and the chains and tensioner blades will rattle! This is also a concern because it means that the big end and cam bearings are also likely to be getting insufficient oil throughput and damage will be virtually guaranteed after a short while.

If it isn’t the gasket it is unlikely to be the pump gear, (Which, incidentally, by 2011 had been changed to the later, phenolic/‘Plastic’ type rather than the earlier steel gear.) because they either work or they don’t! There is no ‘Half way house’ that would cause low pressure. If the gear fails the pump doesn’t spin and there is no pressure!

So that leaves the oil pump itself, which on the 8V’s is pretty much unburstable, and the oil pressure relief valve. One other possibility would be The o-ring on the pick up pipe and in the case allowing the drawing in of air but I imagine you would have checked those when you had the sump spacer off?

Really, at this point, it might be best to plumb in an oil pressure gauge and find out what exactly is happening. Due to their bodywork Norges do run hotter than other models but they are still ridiculously over-cooled which is why the fan so rarely cuts in on them.

Other than that the next step is to start taking things to bits and measuring! There’s no crystal ball for this sort of thing sadly.

@nateshoe - have you found the workshop manuals on this site? See Ex Libris section

Thanks so much Pete. You are truly a fountain of information.
Today I did the test ride as I said with the latest pressure sensor changed.
So I'll do a summary of the previous episodes.
30087km June 2023. Original sensor broken with significant oil leakage and warning light always on:
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Solved with new Hella sensor ?

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No! at 32500km oil warning light comes on again with engine hot at idle.

So Meyle fitted but the warning light continues to come on at idle and when hot

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Changed oil sump gasket, oil brand and filter brand but without solving.
The Pressure oil sensor shows a micro leak from pin.
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33420km 27 May 2024 mounted Oil sensor Facet model 31768780-Z

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Need to adapt the different connector but it's very easy.

Bingo!!  
Now the warning light no longer comes on when idling with a hot engine.  
Let's see how many km it lasts.