[JimD]

My VIN is accepted by RealOEM now so I checked the part number for my head. I have the new part. So I should not have the ticking issue.

I don't think more frequent oil changes will solve a design problem. I do not have experience working on old BMW motors. But I know that infrequent oil changes will result in buildup in the valve train of the motors I have torn down. If the oiling of the lifters is marginal and you let some sludge get into them, they are not going to work as well. If you change the oil more frequently, you may at least avoid the issue longer. Maybe you never get it. But the real solution is parts with adequate oil to the lifters. Apparently that at least sometimes requires a new head. Makes sense if it is an oil flow to the lifters issue. Lifters alone would help but the passages to the lifters matters too.

If you are annoyed by the noise I do not know what you can do but get it fixed for as little of your money as possible. If you are scared something terrible is happening in your engine because it is ticking, I don't think you should have that concern. Oil pressure rises with engine rpm so I think there is good reason to believe the clearance in the lifters causing the noise goes away when rpm (and oil pressure) increases. I don't think we should have to tolerate ticking for what we pay for our cars, even if it is mainly a cosmetic type issue.

One of the reasons I think the lifters are likely to be working fine at higher rpm is that is my experience on old american cars with somewhat worn out lifters and low oil pressure. They would make noise too but it was fairly clear from the performance of the vehicle that the engine was not seriously down on power like it would be from significantly reduced valve lift. In those engines thicker oil helped sometimes but an engine rebuild was the only permanent fix (oil pressure drops in old engines because the clearance in the bearings increases). (thicker oil will give you higher pressure at startup but it also might leave some areas without oil for longer because it will not flow as well, I wouldn't recommend it for a car under warranty)

Jim