Oilpressure

If that is stuck open you usually have oil light at idle right from the gate

By reading original post, there is couple informations that you need to pay attention to.
As you said bike had oil pressure when started up which tells me there is supply from pickup and output from oil pump. Now as you said after few laps your oil pressure drops kinda indicates that when your oil gets hot and thinner than your problem starts!
Usually on the cars that would be sign of main bearings and /or oil pump clearance issues, I am not sure on Ducati but it shouldn't be night and day of difference.

These motors are a blessing and a curse. There are some cool features ( the ability to swap liners and pistons without splitting the case) but there are far more sinister things lurking within. The 2 piece case requires absolute precise alignment or you are going to have main bearing failure. To compound that, they use a 2 piece main bearing which just makes things a bit more critical. The RS motors use 1 pc mains. To build the case right and ensure main bearing alignment you have to first select the correct class of bearing for the crank and the case.

You install the mains with a special tool that presses the halves in place. (I use the 1 pc bearings).
You then assemble the engine and this is where the problem is. If its not perfect, your going to have a main bearing issues. To make matters worse, the case is the chassis which means all the suspension loads are constantly trying to twist these two bolted case halves. That cant be good for precise crankshaft alignment so these things have main bearing issues. Bo13R agreed, that's def some place to look as I said there are different classes of bearings that must be chosen based on case based on case hole dims and crank journal dims and you still need to check them which I am sure Donald did as he sounds like he certainly knows what he is doing. He will find the the cause I'm sure.
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I am in a different time zone, so a little bit late with my reactions.

First the restrictor. My European bike has a restrictor too, but looking at your pictures it is further down the line after the canals to the side cover (pressure switch and crankshaft).

The pick up tube may be the answer. I never realized that there is a screen inside, so I never opend it. Today I did and there was quite some sludge in it. It wasn't blocked totally but it is possible that after a few high rev laps it can't produce enough oil anymore. It would explain too that warming up the engine didn't show any problems.

Finally some pictures of this expensive lesson. As you see I use Carillo conrods. That is because a few years ago I had one similar to to the picture of Don14r.

Was the pickup assembly not checked prior to reassembly? The RS pickup uses a dual filter element (which wouldn't have helped in this scenario) So new main bearings, rod bearings, crank or repair, rod needs to be looked at, etc. How about the liners? Not terribly costly but a pain in the rear none the less.

If it is going to help, just look what member Dezi and I found in our pickup screens while addressing water pump plastic gear problem. Keep in mind, my bike only has 2300 miles and my water pump gears did not fail. With that said all that crap had to be in the engine from factory assembly!

Yes the plastic water pump gear saga is a bit oversimplified. On the last rebuild (17,320 miles) the plastic pump gear assembly looked brand new. I suspect that the folks who have has plastic pump issues either had defective materials in the gears themselves or contamination that led to the demise of the gear material. A properly built and maintained motor isn't going to have any issues with the plastic pump gears. Additionally, keep in mind that the longevity of the pump bearing will be compromised with the metal gear. For the same reason aircraft are going to lightweight composite propellers to extend hub and bearing life, that pump bearing benefited from that plastic gear. The RS motors with the metal gears don't have the same considerations as a long life street application.

I don’t think you stuck a piston...

Looks like it straight welded the H rod to the crank

As far as the left main being worn yeah imagine how hot the oil was when it got to that main (more like water by then)

Can you please post pics of the liners pistons and that restrictor???

endodoc said:

Yes the plastic water pump gear saga is a bit oversimplified. On the last rebuild (17,320 miles) the plastic pump gear assembly looked brand new. I suspect that the folks who have has plastic pump issues either had defective materials in the gears themselves or contamination that led to the demise of the gear material. A properly built and maintained motor isn't going to have any issues with the plastic pump gears. Additionally, keep in mind that the longevity of the pump bearing will be compromised with the metal gear. For the same reason aircraft are going to lightweight composite propellers to extend hub and bearing life, that pump bearing benefited from that plastic gear. The RS motors with the metal gears don't have the same considerations as a long life street application.

Click to expand...

My reason for mentioning plastic gear thread was only due to having pictures of crap found in oil filter pickup screen...

The pictures of the liner and piston of the vertical cilinder. Horizontal looks exact the same. The cilinders are Nicasiled and the pistons coated. As you can see there are seizure marks, but no serious damage. The liners are not scratched, you can't even feel the marks. I think lightly hone (English?) the liners and polish the scratches on the pistons and maybe new piston rings.

Pressing the bearings out and in the case will be more of a challenge. I didn't figure out yet how to do that. Of course heating the case but I don't have a tool to press it out and in. Any idea's?

maybe a dumb question but the same tool is used to install the bearings and you said the motor was rebuilt. So where’s the tool that was used to install the main bearings during the rebuild?

This is the correct tool for removing and installing 1 and 2 pc main bearings. If you have access to materials, one could easily be manufactured on any precision lathe or you may get lucky with a bearing press kit that has a correct fitment however, this is a fairly precise tool so that would be a stretch.

It may be easy to use a bearing press kit and just modify the cup but you would still need the ability to precisely measure and you would still need access to a precision lathe but it would be a lot faster and easier than fashioning a complete tool.

Dhuigen said:

...Horizontal looks exact the same. The cilinders are Nicasiled and the pistons coated. As you can see there are seizure marks, but no serious damage. The liners are not scratched, you can't even feel the marks. I think lightly hone (English?) the liners and polish the scratches on the pistons

Click to expand...

You are NOT to hone Nicasil sleeves !!! It’s way too thin to hone. You would be left with steel sleeve and iron ring. Don’t do it

I have polished pistons before but never coated pistons. It’s a shame the factory wants to .... us on replacement parts : (

*Pistons are ‘ok’ - Back to why it welded the crank!

What’s the preferred method to “clean up” the walls? Carrillo can do pistons.

I have taken non coated pistons to a belt sander using a very fine belt to do the edges before (like of a motor broke a rod and the guy had a spare piston) or used 600 grit paper but polishing the skirt is dangerous because you don’t want to mess with the taper. Not to mention the shape as not all pistons are round to start with

I never cleaned up coated pistons as the coating is softer than aluminum. Prolly need to have them re coated right?

My bearing removal kit is based on impact not press, but I have a lathe of my own. So I think I manufacture something. I am retired and still in covid lockdown, so plenty of time.

Btw, the whole rebuilding was a covid lockdown project. The engine was OK, but after 5000 race kilometers I wanted to check it. The bearings looked like new and de clearance was OK so I didn't change them. And as I said before: I didn't realize that there was a screen inside the pick up. Expensive lesson but a serious crash is more expensive and last year there was no racing (so no crashes) as well.

Thanks for all your reactions so far

Got it, good luck and let me know if you need any specs on the tool or any other assistance

Yay I was wrong about the restrictor : )

These cases I have here are so broke lol it’s not easy to figure out the circuit

Restrictor IS definitely for the rest of motor and trans whew

Crank is not restricted yay

Still does not explain dudes big end failure.

1) Donald you said you reused all the bearings right?

2) What do you use for supporting the rods when the bolts were torqued?

3) What did you torque them to and how many degrees after?

I think he’s already concluded that he had a sump blockage. From what he wrote I’m concluding that he never inspected the pickup filter assembly and it was in fact compromised yielding terminal results. This is the wedge tool to torque the rod bolts to spec. You need this tool or you need rod jig or for our Harbor Freight members, a vice and some firewood.

Dhuigen said:

My bearing removal kit is based on impact not press, but I have a lathe of my own. So I think I manufacture something. I am retired and still in covid lockdown, so plenty of time.

Btw, the whole rebuilding was a covid lockdown project. The engine was OK, but after 5000 race kilometers I wanted to check it. The bearings looked like new and de clearance was OK so I didn't change them. And as I said before: I didn't realize that there was a screen inside the pick up. Expensive lesson but a serious crash is more expensive and last year there was no racing (so no crashes) as well.

Thanks for all your reactions so far

Click to expand...

endodoc said:

I think he’s already concluded that he had a sump blockage. From what he wrote I’m concluding that he never inspected the pickup filter assembly and it was in fact compromised yielding terminal results. This is the wedge tool to torque the rod bolts to spec. You need this tool or you need rod jig or for our Harbor Freight members, a vice and some firewood.

Click to expand...

Yup, it sounds he had crap in oil pump pickup screen. If you don't mind can you please post picture what you found!?
Thanks