We did quite a bit dyno testing with stock filter,K&N,and stock filter with element removed just the wire screen.The K&N was rich as hell. I think a lighter oil and cleaning more often is better than the sticky stuff they come with.

Well I'm running the screen only in mine since I've stuck the ram air on, but before when I had the K&N in I would have cleaned it every other trackday. The K&N oil is very sticky from memory.
I did filter and exhaust upgrade at the same time, so had to rejet mine, and lift needles iirc. Was coming in very rich.

The oil they come with is like treacle,meant for road bikes I think.I have a couple of different ram airboxes.One has nothing at all over the carbs,but there is a gauze further up the intake.Its quite a lot bigger than the modified standard box.Havent tried it yet,waiting for the weather to clear up so we can get to the dyno.

I'm forever emptying rubber marbles out of mine! can only assume its coming off the front tyre as I'm not that close up anyone elses arse!

I ran mine at the Manx last year,we washed the screen out a couple of times with brake cleaner.The stuff left in the wash tray would have wrecked the motor.There seemed to be a lot of fuel residue from stand off vapour from the carbs.I think this new has more clear space above the bellmouths.

God bless brake cleaner, I use it for EVERYTHING.

I just bought a Wurth pump,and 10 litres of fluid.Its like an up market garden sprayer.