A wet sump system has a pan or cavity that oil drains to by gravity where it is picked up from by the oil pump. A dry sump system uses a second pump to pick up oil from the crankcase and move it to a storage tank where it collects and entrained air bubbles can be eliminated or reduced. So, the R3 is a dry sump system. Engines that run inverted or in any orientation for that matter use multiple pickups and/or flexible pickups that swing based on G force.
As to if captured air in the oil system will show pressure on a gauge; YES! Add to that the response time of the oil pressure sensor and you can have low or no oil pressure intermittently and not know it.
The oil pick up in the tank will, should not, be an open ended tube as the those are prone to cavitation from swirl (like water draining in a bath tub creating a swirl and then air goes done the center of the vortex. It most likely is a tube laying parallel to the tank bottom with multiple holes in the side or bottom next to the floor of the tank. But I have not cut one open so it may differ.
Based on Steel's explanation of what happened, I would hazard a guess that the cam bearings in the head seized from lack of lube. This would lead to the cam chain jumping off, breaking, or shearing of the lower sprocket key. A main or rod bearing failure would likely lock up the motor leaving Steel with a wild ride till stopped. The fact it has no compression means it turns over but without cams rotating, no air in or no compression due to open exhaust valves, and of course those that can't close due to bending from contact with the piston crowns. Likely, all pistons are toast as well as the head. Main and rod bearings may show signs of distress as well.
Carpenter may have a point about wheelies leading to the failure. The passages to the cam bearings are very small/restricted so that they receive no more oil than needed. If they are too large, the excess oil fills the head so that the valve springs and cams run submerged in oil. This leads to excessive oil consumption and high oil temperatures. Additionally, the oil is whipped into a froth that becomes largely air (like whipped cream) which then leads to oil related failures as the engine circulates less oil and more entrained air. On the other hand, lack of lube to the cam bearings will degrade the bearings and they will eventually fail.
What is less obvious is that the Carpenter head has much greater valve spring pressures which puts greater stress on the cam bearings. They may or may not have changed the oil passage size to increase oil flow to help compensate, or may have found that doing so is not needed on the R3. ???
If I were to wheelie my R3, filling the oil tank to the point just short of blowing the cap off would be first on my agenda. (Or perhaps change the cap to a locking one that can't blow off and fill until it does puke oil when hot, after which you would know how much oil to put in.) Much better to puke a little oil out the breather than have a catastrophic failure.
Reminder here: this is an opinion based on my knowledge and experience: I have not examined Steel's motor. And I do not imply that Carpenter is at fault in any way.
As to if captured air in the oil system will show pressure on a gauge; YES! Add to that the response time of the oil pressure sensor and you can have low or no oil pressure intermittently and not know it.
The oil pick up in the tank will, should not, be an open ended tube as the those are prone to cavitation from swirl (like water draining in a bath tub creating a swirl and then air goes done the center of the vortex. It most likely is a tube laying parallel to the tank bottom with multiple holes in the side or bottom next to the floor of the tank. But I have not cut one open so it may differ.
Based on Steel's explanation of what happened, I would hazard a guess that the cam bearings in the head seized from lack of lube. This would lead to the cam chain jumping off, breaking, or shearing of the lower sprocket key. A main or rod bearing failure would likely lock up the motor leaving Steel with a wild ride till stopped. The fact it has no compression means it turns over but without cams rotating, no air in or no compression due to open exhaust valves, and of course those that can't close due to bending from contact with the piston crowns. Likely, all pistons are toast as well as the head. Main and rod bearings may show signs of distress as well.
Carpenter may have a point about wheelies leading to the failure. The passages to the cam bearings are very small/restricted so that they receive no more oil than needed. If they are too large, the excess oil fills the head so that the valve springs and cams run submerged in oil. This leads to excessive oil consumption and high oil temperatures. Additionally, the oil is whipped into a froth that becomes largely air (like whipped cream) which then leads to oil related failures as the engine circulates less oil and more entrained air. On the other hand, lack of lube to the cam bearings will degrade the bearings and they will eventually fail.
What is less obvious is that the Carpenter head has much greater valve spring pressures which puts greater stress on the cam bearings. They may or may not have changed the oil passage size to increase oil flow to help compensate, or may have found that doing so is not needed on the R3. ???
If I were to wheelie my R3, filling the oil tank to the point just short of blowing the cap off would be first on my agenda. (Or perhaps change the cap to a locking one that can't blow off and fill until it does puke oil when hot, after which you would know how much oil to put in.) Much better to puke a little oil out the breather than have a catastrophic failure.
Reminder here: this is an opinion based on my knowledge and experience: I have not examined Steel's motor. And I do not imply that Carpenter is at fault in any way.