TOPIC:

I found this filter and have no idea what it came off, but it fits tight and I am thinking about keeping it. (I am also installing a good external filter).

Any opinion on if it could create any problems restricting fuel supply to the six cylinders, and if I should go for more surface?

err, which filter?
Was there a picture?

If it's an in-tank filter (petcock style) then you could do a timed flow test (into a large cup or similar tlo measure the same volume) and compare to the OE filter.

That's the weirdest thing.... The picture was there!!!!

I don't have oem filter, so can't compare to anything..

Looks like it only filters the "Main" supply. Filtering the "Reserve" would be my concern cuz debris in the fuel will fill the well around that port, in the fuel body - soon as you open the "reserve' - you know where it's going ! That's why having an external filter is critical.

Yes, of course, I ignored the reserve now for those two reasons: 95% of the time I will most likely not run on reserve, and I will have an inline external filter and it will take care of those rare times.
I think many modern bikes don't even have petcocks, so the only filters they use are those external ones? I know my Vmax does have just that one. So, I'm leaning towards ignoring any petcock mesh. But since I found this one, I thought why not! An extra barrier for the 95% of the bikes operation. Just wondering if this one would create a restriction, if anyone experienced would have a feeling for it looking at it with a naked eye. I might just install it this way and see how the engine runs with and without it.