At last got the better air filter for the Cali 1400 the filter is expensive 60 pounds it is washable just re oil and use again it takes six times for you to recoup your money back its a Bmc air filter no Fm 373/01 contact them at bmcairfilters.com it looks like the racing filter on my wife S4 monster so it will last for years looking forward to fitting it and see if gives any more power with the Adace pipes all the best Derek.
Done a few miles on the Cali with the new filter seems a lot quicker off the mark not been able to check top speed yet can’t do that in Glasgow once I get a chance I will let you know might be due to the Audce pipes also all the best derek.
Top speed seems improved also gets there a lot faster just need to do more miles on the old girl she’s going to be 5 years old in July all the best Derek.
Tried the top end on the way back from Ousby fully loaded with Helen on the back gave a couple of Honda riders a shock a big Cali flying past them .
will let you know might be due to the Audce pipes also
So actually you can’t be sure which has made the difference? One thing about reusable oiled type filters you have to avoid over oiling, easily done then it’s as bad as if it’s clogged up. Also they get dirty quickly and air flow drops off. There are graphs on internet somewhere where somebody tested a whole bunch of different filters using a special air flow testing machine, which included introducing dust to simulate working life, all (I say ‘all’, two makes?) the reusable mesh and fabric in oil types did poorly overall, yes produced noticeably increased air flow initially but quickly clogged up and restricted flow after a modest amount of use. The best performers overall and especially for long term were the OEM paper filters. I have used K&N’s in the past and can report that they don’t last forever. The cotton fabric gradually disappears (sucked into the engine?) leaving just the mesh behind, which will allow sand sized grit to pass. Cleaning and re-oiling can be quite tricky to do properly (washing, drying etc.) if not done properly, and/or if over oiled, filter will perform poorly. In retrospect, much quicker and easier to chuck in a new paper filter.
Just IMHO … 
Sorry mate riding bikes since 1975 changing exhausts and air boxes also better air filters seems to work for me I tend to keep the air boxes mainly standard but let more air in to the engine back in the 70s-80s we all did it thinking it would give more power but with fuel injection these days you can only go so far just passing on mods done to new 1400s so it helps other owners all the best Derek ps the new 1400 also can spit back oil back into the air box always clean the drain pipe hole at every service .
During the lockdown I got the Dremel out and enlarged the air holes in the air box the rubber snorkels were binned when I fitted the Bms racing filter they make the air holes smaller the 1400 needs air to breathe on the wife’s 916 monster we have the open racing air box with racing filter so I know it works on the 1400s they spit oil back into the air box so you can’t do away with the air box can’t do any more on any of the bikes till the lockdowns over praying to the gods of Guzzi be safe out there all the best Derek.