nearing on 10k, maintance question

[Lpfm1990]

after a little over a year, im nearing in on 10k on my 2015, and going to do some mods (adding in a usb outlet for my phone) and maintance, and looking to see since im going to be in the bike, if im forgetting anything (not really into ripping apart and putting it back together, just to take it back apart, lol) but im going to be doing the air filter/drilling out the airbox, because why not??? but from reading, since im in that far, i probably should be doing the spark plugs (which makes sense since she has been doing an odd backfire once in a while, and other day started on only 3 cylinders for about 10 seconds before the 4th hole lit) so between the air box/filter and plugs, is there anything else i should do/look at? the oil is good i just did that 2k ago.

also. since im doing the air box, ive already got a 2bro's exhaust, ais block offs, and pcv with marthy's sport rev b prg loaded, its running rich, so im thinking i should be ok with the extra air? i know i need to get it put on a dyno at some point in time.

thanks for the help/info in advance!

 

[Final Impact]

The older sibling the FZ6 the caps to the high tension lead from the coils has been known to get loose and induce harmonic vibes into the engine from say 4500 rpm up. It is waste spark and the loose fit changes when the spark is delivered to a cylinder set.

Hold the wire and turn the cap clockwise. It should tighten within 1/2 to 1 turn. If it does not, unscrew it, cut off 5 mm or so and thread it back on.