I searched the forum and there is alot of info on this subject. However, my bike is not nearly as modified as most of the bikes that are discussed. Currently it is completely stock. I have a Bill Blue special tm33/34 carb which I picked up used from another rider on here. I also have a Big Gun Evo -R full exhaust. I am leaving the air box lid on, call me paranoid but I use this bike to drive me to and from work everyday I can, as well as I also drive it out in the dirt and mud and I dont want get dirt or any other crap in the engine by taking the lid off.

So what jets should I use? Currently it has a 140 main and 37.5 pilot but was setup to run bill blues 331 which I dont have yet. I have quite a few differnt sizes starting at 127.5 up to the 140 and a 40 pilot.

Thanks for helping a newbie rider out. you guys have been great!

 

Try #132 main and #35 pilot. Those are the stock settings for the KLX300R.

 

What I would do is call bill blue.

When I contacted him he said that he could get me in the ball park on the jetting. Then work from there.

Post your findings if you would, I have that mod on my grocery list. Best of Luck.

 

since you have the full exhaust i'd go with the 135. when i had my full muzzy i was running the 137.5 but i think that was a tad rich. you did at least take the snorkle off right? if not take it off and enlarge the hole some. right now i have a huge hole in mine(4x4 if not bigger) but i think it's too big since deep water gives me some stuttering.

 

That might be due to the carb vent lines going underwater, unless you have already done the carb "T" mod.

 

i wish I had waited patiently for all of your great help prior to puttping the carb in. The bike runs but back fires horribles when letting go of the throttle.

I will change the main jet to 135 and see how it works. It is running way to rich...

Thanks,

Steve

 

When the carb is installed are the jets under the black cover on top or under the cover on the bottom of the carb?

 

Under the cover on the bottom. Careful of the little spring in there when you remove the cover - mine went flying.

I'm curious to see what you end up with. I had the same backfire and found that I was too LEAN with a 140 main on a basically stock bike (I have an HMF pipe). After you put on the aftermarket exhaust you'll want to rip out the air injection plumbing. It wasn't until after I removed that that all my backfire problems went away. I also had to bump the jet needle to the richest position.

A couple days ago I put in a 142.5 jet and dropped the jet needle back into the middle position. Runs great! Even had it up to 10,500 RPMs afterwards.

 

What did you use to plug where the air crap goes into the engine at the front of the cylinder? Also what did you use to plug the hole in the airbox?

I am going to give it another try tommorrow. it got to dark to finish. If I cant make it work tommorrow then on wednesday I will take the bike to a motorycle mechanic and have them setup the carb. Either way I will let everyone know the end result. The bike has to run on Monday so I can get to work though. If anyone is from or near Bufalo NY and is interested in making some cash. PM me. I would pay someone with profesional experience to make it work.

 

What is the "T" carb mod?