plugs and filter
 

i got a 2006 F4i with around 15Km on it.
i am pretty sure its still running stock filter and plugs.
and now i'm getting it ready for the season. already tighten the chain and she is all clean ready to go, did an oil change and bleed the brakes.
but i am a bit iffy about the plugs and filter
should i change it or let it go, seeing its just over the 15Km mark, how long are they good for?

and if i should change, what is better than stock?
i have been looking on ebay but i dont know, they are so-so

any tips?

At 15k I would change the filter for sure. Go with OEM, they work the best and actually give the most power on an unmodified bike. As for plugs, if its running good now, you could probably go another 5-10k. Also get stock plugs when you change them eventually. Honda designs their engines to be run with specific parts, changing to a different plug isn't going to gain you anything and would most likely hurt performance. Plus I'm not sure about the F4i, but on my 954, top of the line Iridium plugs are standard.

According to my Haynes manual (Honda CBR 600 F4 fours 1999-2006) the plugs for your bike are: NGK IMR9C-9H or Denso VUH27D. Gap is 0.8-0.9mm. I would definitely change the filter for the little amount they cost. Hope this helps!

hello everyone
thanks for the input, i guess i should mention i have a cut and gutted muffler, i dont know if that adds any power, i did it mostly for the sound and look.
i will goto the dealer and order a new filter. just have to run it till the tank is empty as i just filled up this morning.
and followup question, i have heard a lot of about sea foam products. i ran it in my car but i had to spray in the intake and rev the engine. how do you do this on a bike? or is there another way?