New (to me) KLX 300 - Some mods already done - Few Questions

Hello everyone -

I am a long time streetbike guy. Used to ride MX when I was in early teens. Anyway long story short had a few things happen that I decided it is time to get off the streets, but I am not willing to give up on its back to MX time.

Anyway I picked up a 2006 KLX 300R that is cherry. Has like 8 hours on it.

Came with larger rear sprocket (52 I think can't remember for sure)

FMF Pipe

Othewise pretty stock

I realized shortly after I got it to Chicago (came from Colorado) that it needed some serious help in the fuel and air department. Seems when the pipe was put on they kept the stock pilot and needle setup. Turns out this bike was shipped with the California emissions so no adjustable needle and the airbox was a joke.

First thing I did was remove the airbox completely. Installed a new K&N filter.

Next pulled the whole carb apart and cleaned it all. Installed the FMF jet kit and drilled out the hole as instructed. Replaced the needle and jet.

New spark plug and full synthetic oil change.

After I put it back together wow what a difference. This is a new bike now!

Anyway the questions are as follows. Is there any other relatively simple modifications you guys would suggest?

Also I really want to dress up the looks a bit. However it seems when I look for graphics kits I never find anything cool (monster or something like that) for this bike. Does anyone have any recommendations on graphics or where to look? It does not have to be a factory racing by any means just would like a cool looking complete set.

Thanks in advance

Was just thinking that another question is can I use a graphics kit for any other KLX without fitment issues?

Also should I replace the airbox I removed or this another option to order. That thing is ridiculous and it starves the bike for air, but I am a little concerned about dirt and mud and water getting in there?

did you change the crankcase vent hose? Look up planetklx on the net and that will tell you how to change out the hose. If you are worried about water you can leave the crankcase breather hose connected to the air box but take the rubber plug out of the hose just where it comes out of the motor. If you have taken the lid off of the airbox I think that is about as much as you can do with that . Did I understand you have a fmf exhaust? Do you still hace the stock header pipe on if you do change it out for an fmf header or four stroke works header. I have a 04 with a full big gun exhaust system with a dynajet kit and opened up crankcase breather tube and it really is a different machine than when it was stock. I did go one tooth smaller on the front sprocket to get a little lower gearing and it is easy to change back if I need to go back to the taller gearing. The 300 may not be the hottest bike out there but it sure seems to fit me well happy riding.

Thanks sdd

Do you know if the graphics kit for any other klx will work for our bikes?

I haveba full fmf kit on there already and love it. Not even sure what he crankcase vent hose is. Do you have a link for me by any chance?


The KLX300 is not a super powerful machine for it's displacement. You can throw money at it and get some extra kick out of it, but if you are wanting it to compare to MX bikes I think you will be disappointed.

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