lmao, I tell you what einstein (captain)- if your stock 300 header, or any other stock kawasaki KLX300R header is larger in diameter to the 250S stock header, I will personally RIDE my '09 KLX250S to your house and sign the title over to you. is that a deal? I presume you won't have the ***** to admit that you're wrong when you get the answer from fsw. Just one question, why would you buy a $160 FSW header when YOU say it was the same size and modeled after a stock 300 header that can be had for free to meer dollars online? But then you say you've got a 300 header on your bike? Do you even know what type of exhaust header you have? Doesn't sound like it.

75vette-
some of these guys you're corresponding with are newbies. I've owned TWO KLX 250S' and have been through both of them several times. I KNOW what I'm talking about. Some of these newbies know not what they are talking about. This is a perfect example here regarding this silly, minute subject. EVERYONE knows these two bikes' headers are identical in diameter. Why do you think that it is the gospel around 300 roundtables to yank the oem header off and throw it in the garbage? Because it is too small for the 300 to breathe. The aussie KLX does get the 300 header stock, but it is still the same size in diameter. Anyone who says the 300 header is larger in diameter is flat out ignorant. It's common and known fact that it is the same size, just a bit longer. I don't really know what else I can say to help you out. If you're expecting big power gains out of the 300 header you evidently have coming, you will be sadly disappointed. Like I said, the Muzzy header is the largest one available and you probably should have bit the bullet and got the full system for the maximum performance. and to be clear, the FSW header is larger than the stock 300 header and it may work with your Muzzy slip-on. but let's remember that this is an aftermarket header and has nothing in common with a stock 300 header except for length.
good luck.

 

I think you'll find this article pretty helpful regarding the KLX series of 300's and 250's. In particular, pay close attention to the 12th paragraph and then ask captain to measure his KLX300 header to see if Larry Roeseler is just rambling as well. lmao

http://www.motorcycle.com/products/s...mods-3510.html

 

Blank. ????

 

IG, I think you're aliterate.

This is what I said: larger, as in larger than the stock 250S header like theirs is.

I'm saying that the FSW 300 header is definitely larger than the stock 250S.

Where in there do I claim that the stock 300 header is larger or the same size....I say ask the guys at fourstrokeworks.biz, because they ARE NOT YOU.

My 300 header from FSW is most definitely even visibly larger in diameter.

I don't speak to the stock 300 header, because I do not have one. My FSW header fits quite well with my FMF can that I know you love so much.

I will take it off and take pics for anyone who's interested in seeing the difference. Just let me know.

Here's my setup: '07 klx250S, Bill Blue TM33 pumper carb, bored to 34MM, motion pro vortex throttle, FSW 300 header, FMF Powercore can, air lid and snorkle on. 145 Main jet, 40 pilot jet, needle valve is one step richer than stock: 640 Q-0, jet needle is stock, 1.5 turns out on fuel screw, (it's not an air/fuel screw, to clarify, just so you don't say that to someone who knows better and make yourself sound like an idiot...air screws are two stroke carbs) White Bro's air filter, 91 octane. Bill blue stainless front brake line...world of difference over stock.

Yeah, IG, I'm a newbie. Go fix your dented muzzy and turn your "air/fuel screw" out another .5 turn, instead of replacing the pilot jet like you should.

 

Don't let him get to you captaintrps.

Your set up looks just fine to me.

 

you say 300 header, a little late for backtracking capn. this whole discussion has been about the 300 header in which this guy has bought and is expecting in the mail. no one ever mentioned fsw header, we don't care about that header.

fyi, I'm at 2.25 turns out on my a/f t-screw. I think your newbie knowledge is even less than I gave you credit for. That is more than under the requirements to go up in pilot size. Ask how many KLX owners on this forum have changed out the stock pilot; I'd say you could count on one hand how many have. The Dynojet kit doesn't even say anything about changing out the pilot because it just isn't required for 99% of applications. But hey, nice backtracking try nonetheless. Now YOU know the 300 header is the same diamter as the 250's ; I see that article I posted served you well. And HEY, thanks for visiting my profile, I'm flattered. LMAO

edit: one more thing, you make fun of my "dented" full Muzzy header. Yeah it has a couple small dents in the end of the header that are barely noticeable. But even with the dents, it will flow more than your cheap little future rusted fsw pipe will ever dream of. You make fun of my full stainless Muzzy system that I got for $100, but Nobrakes along with around three pages of other owners said the dents would not affect flow since they're so minor. You're mocking someone who got a full Muzzy system for $100 who Nobrakes called "pristine" when you just paid $160+ for just a steel header alone. But hey, at least you got an aftermarket pilot jet. LOL
You should study the last two years of this forum in the search, you could really learn alot.

 

What I'm confused is that back in 2006, all the exhaust that we were buying was made for the KLX300R as nobody had acknowledged the 250S at that time and everything fit perfectly other than small minor issues like the chick peg hitting the Muzzy.

I also have the powerbomb which is bigger than the 250S header but fits into the same HMF Muff.

 

Come on guys, lets move beyond the petty arguing. I thought it was clear that captntrips was talking about the fsw header, not the klx300 stock header. Also, captnrips, no need to get personal and resort to name calling. Either way, it doesn't really matter, please just agree to disagree and move on.

 

NB, he went back and added the "fourstrokeworks.biz" to differentiate himself from what he had lastnight. He edited his original post, which just stated the 300 header which is why I put up my '09 to him if he could prove it. After I posted the article regarding Roeseler's take on the stock header, he went back and backtracked his original post. He even mentioned FSW modeling their header after the stock 300 header. He recognized he was wrong this morning evidently and edited making it look like he was talking about the FSW header all along. Well, everyone knows the FSW header is larger, if it wasn't what would be it's worth? Nonetheless, I just want to make sure these newbies know what exhausts fit and which ones don't. You and I know, but some think the stock 300 header is larger in diameter and what not. I know it's petty stuff, but when you receive it in the mail and install it and it won't fit or it isn't any different than something you took off, well, then the petty stuff is huge.

 

Sorry, I just posted this venting about how it sucked to have every piece f the puzzle but one and it has turned in to a big argument. Only question I have about this is there any benefit of going to the 300 header or should I try and return the 300 slip on and just get the 250 slip on?