Have you done the Air snorkle modification? (you cut the top 1/3 so that more air goes into the filter)
Are you going to dusty places?
Are you going to use the bike around town, or in the field?
Is you bike a Single spark or Double?
Are you using the Normal BMW spark plugs?
Do you have a Stock Exhaust?
Is this a Perfomance Mod? ie do you want more power?
And are you running a Dobeck Fuel Nanny? if not and want one then let me know as I will be selling my spare one, installs in minutes and then vooom. F650 Ride the World - A journey of Global Proportions
I have the Dobeck Fuel Nanny Fi-1031ST installed on my bike and it runs fine with the BMW filter, But I have drilled 3, 1/2 inch holes near the battery so that I can get more air in to the Box no water gets in that way
this IS BEFORE the actual filter of course NOT after it. I don't need the K&N it's way to expensive for what it is, you could get one of those Fully Sponge filters from Touratech that you can clean (£30), you don't have to buy their hugely expensive cleaning solution just use Diesel, but I do get lots of power from my bike with the stock filter.
I purchase 3 air filters at a time along with the Oil and Spark service kits from Motorworks - BMW Motorcycle Spares - home
they are a great company and will bend over backwards to ship you parts ANYWHERE in the world, and are CHEAP.
Think the guy I deal with most is TED, nice chap very smart person.
Now the sponge is mostly there so that you don't dilute the fuel with too much air, think that's called runnning lean. But I think that the Engine will only hold so much air anyway so it shouldn't make much difference, try it without it and if the bike runs fine then all well and good, if not insert it into the filter. But as long as you have the main filter in place you can't do any damage to the bike, but please make sure the Filter is seated correctly before putting everything back together.
Oh and Don't forget you can ride the bike around the block a few times without the Faux Tank Panels on, to save time if you do need to insert it.
NICE CHOICE OF BIKE BY THE WAY