I was just curious as to what mods gave you the most performance gains. From what I gather its the
1.) Carb mods, basically a dyno jet kit with the air/fuel mix. screw turned out 2.5 clicks.
2.)Free crak case breather mod.
3.)13T sprocket
4.) Drilling out exhaust, or putting a very expensive Muzzy on it.
These are the basic things that make the KLX scream correct?? Which one makes the most differance.
Also will that 13T gearing slow it down on the road from the original gearing? I think I will go with the 13T anyways because everyone swears up and down by it.

 

The stock gearing is so tall, you don't get the horse power to the road. Scat can tell you, he has went to the 13t, and then to the 13/45 combo. He has not made any other mods, and seems very happy. I think Scat is getting 58mpg.

 

Yep. The 13t helps the most right away and it SPEEDS UP the highway performance of the bike because you can actually use the upper RPM range (where the peak HP is) that you couldn't get to before. However, doing the carb work, opening the airbox and exhaust, and doing the crankcase mod made a VERY REAL difference in throttle response which for me is even more important. The bike just "pops" now where it lagged before.

My dealer just got (and then sold within 1 day) his second KLX250S. It was purchased by a friend of mine and I've already got him ordering all the goodies His other ride as a BMW F650 so he's loving the KLX's light weight but missing the power.

Before we mod his all up, we'll do a side-by-side comparison between mine and his bone stock bike. That should be interesting.

 

In order of biggest performance impact

1) Gearing change. I'm at a 13/45 and it's perfect compromise for street & road use. The engine is smooth enough that 8500RPM at 70mph isn't too annoying. I may go to 14/47 later on for better chain and sprocket life.

2) Muzzy exhaust - this includes jet kit & KX snorkle 3-4 HP over stock?

3) Crankcase vent hole. Noticeable improvemnt in throttle response. 1 HP?

4) If you don't get a Muzzy, drilling the throttle slide, 125 main jet, adjustable needle, 1/2 hole in exhaust baffle, and KX snorkle is a great inexpensive mod. 1-2 HP over stock and siginificant throttle response imrpovement.

5) New air filter

The 300cc conversion would offer big mprovements after you already have the aftermerket exhaust and other mods. Probably around 2-3 HP?

 

I'm about to order the snorkle,
Todd said he has a KDX 200 snorkle, and I see that you have a KX snorkle. Will that KX let in more air then the KDX, or are they pretty much the same. If it does let in more air, would posting the part number up please.

 

Order whatever Todd says. KX, KDX.... PoTato, PotAto.

 

Don't quote me [8D] Tony found the snorkle. FWIW, it is the KDX200 (among others). Part number is what matters and that's 14073-1577

 

Very happy with this set up. I have to agree with a16tony the stock gearing is to tall, what were they thinking.I am tossing around going to 14/49 combo on the sprockets.I have also done the breather mod by drilling out the air box fitting and after doing that it put my fuel econ. at 59.2 mpg, no complaints their.
Later down the road i will most likly do all the other mods that most of you have done but right now the buget will not allow it. No matter what you do to this bike be just gearing change to full out mods this bike is alot of fun.

 

I know this has been hit on before but since I have put on my Muzzy and have now completed the jet kit finaly.... I have a problem with some bog, but only when I twist the throttle fast. Normal riding is fine. the bog only last for about 1-2 secounds and its back to normal, but it happend evertime a give it quick burst of gas.

Well the kdx 200 snorkle or the air mod help? I have not done anything to the air box or snorkle as of yet. Any thoughts??

 

ohhh and if i do need the kdx 200 snorkle... where can i find it. I have the part number but not sure were to order it from?