Weak oil drainback into oil tank (low volume)...Problem?

I'm trying to figure out what's making this noise with he engine...
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And today I opened the oil tank filler cap while running the engine.
It was spitting a small amount of oil (frothy particles) back into the tank.
It's volume of discharge increased with rpms, but never became a solid flow (like when you open a oil drain plug on a oil pan or thr oil tank, it has a nice "full" flow coming out...) So I'm wondering if this has anything to do with lack of lubrication, causing the strange sound?

Is this normal for the oil drainback to behave like this? Or would you suspect a blockage of some type?

Please advise!
Thanks!

hi nidy sounds normal that ,the return side of the oil pump has much bigger capacity(maybe twice as much)to clear the crankcase of oil, you should get an intermittent spiting of oil because the oil pump is pumping air as well chris

The part of the pump you are seeing(when looking in the oil tank) runs at twice the volume than the half putting the oil in. So yes some bubbles are normal as it will pump some air. Now when the bike has sat and some sumping occurs you will see a nice study stream at the tank for a time till the sumps pumped somewhat dry.
I know you have a lot on your plate right now but if you stick with this chopp to the end you will know the oil system end to end. Keep reading keep working.

Thanks fellas, I really appreciate the advise!