No Problem
If you want to replace the filter with a free flowing type K&N model #DU-0100 is a direct replacement for the stock Purolator 521172/A that comes in the Electra.
Remove the airbox and filter from the bike, there are two bolts hidden behind the battery which needs to be removed to gain access to them, they hold the battery box in place. Remember ALWAYS disconnect the negative battery terminal first and replace last when removing any battery, this is to safe your electronics. With the airbox in hand place the air filter in place and mark a line at the smallest diameter that can be obtained by moving the filter around against the air filter cover mounting bosses. Now take note of the location of the mounting bosses on the back of the airbox, you do not want to remove them while drilling. Take a 1/2" drill and drill as many holes as you can inside the line you marked and the factory inlet hole. You will want to keep the ridge around the factory inlet for support, so don't drill to close to this. If you use a twist drill be ready for it to grab when you break through. Now take a razor knife or a single edge razor blade and carefully remove the remaining material between holes where you can, without removing any mounting bosses or the ridge around the factory inlet. With this complete it's time to turn your attention to the inner wall between the filter and the carburetor inlet. Since air does not like to turn corners remove this also leaving a small ridge along the bottom for support. do this to both sides of the airbox. That should be it, so reassemble carefully and don"t forget the battery ground wire that was attached to the top mounting bolt on the back side of the airbox. If you forget this you will have no power.
Don't forget to check your jetting, if your located above 4,000 feet above sea level you probably will not need to change the jetting. If your between 2,000 and 4,000ft. vertical you will need to go up from the stock #110 main jet to the #112.5. If between sea level and 2,000ft vertical try going up two sizes from #110 to #115. If you have problem in your midrange look to changing the pilot jet since the needle and needle jet are fixed. Readjust your slow speed mixture with your idle jet adjustment. Set the idle speed last, I find around 1000rpm's to be best.
If you have further questions or problems contact me by e-mail.
Happy Cutting,
Greg