So I picked up a 300 header pipe of Ebay. Question is will it work with my 250 muffler? I did a search, some say yes others say no. I like my 250 muffler after I removed the spark arrester and recapped it. Not loud so wouldn't mine continuing using it.

 

For a 2006 & 2007 it will not fit. I suspect 2008 and up also.
The KLX300 header pipe is necked up (larger) to fit the larger inlet in the KLX300 silencer.

Photo of KLX300 header pipe & KLX300 silencer below





Doug

 

Want to sell your muffler Doug?

Yes the bike's an 08

 

Not for sale
If you do a search on e-Bay they sometimes show up

Doug

 

I believe the KLX300 header is also about an inch shorter or longer than the KLX250S header. I had one, but don't remember which it is, but I do know that it is specific to the KLX300 muffler.

 

I first thought they would be the same. If you search on Ebay for a KLX300 muffler lots of listings for aftermarket that say "fit KLX300/250".

 

Since I think it's going to be impossible to find a KLX300 muffler what do you guys think of this one? Shows the application for both the 300 and 250 on ebay which is a bit confusing.

1994 2007 Kawasaki KLX300R O Series Slip on Exhaust Pipe Muffler 03 8300 | eBay

 

Ok, Ruggybuggy - I'll speak up for you.. I wish those members that have first-hand knowledge of the 300 exhaust on a 250 would speak up - Hey ZENO, you still here?

Firstly, all the info you need is in here but you'll have to search for it.. There are real mistakes that can be made. I own both a 07 KLX300R and a 2012 KLX250S but I have not "mixed and matched" the exhaust systems -

So this is what I know and what I think I know:
Only the entire 300 system will bolt onto the 250. 300 headers are longer and the slip-ons shorter than the 250's, or some such...
The DG silencers slip into the stock 250 header - not a 300 header. My DGR is this way..
The FMF silencers for the 250 require that you remove the seal from the 250 header - my PC4 is this way..

 

+1: the KLX300 header and muffler bolt-on to a 2009 KLX250s without any issues. I found a complete KLX300 stock exhaust system on eBay for $100.

I'm fairly certain a KLX300 muffler will not attach to a KLX250 header (the KLX250 header I.D. is too small).

You *may* be able to attach a KLX250 muffler to a KLX300 header, but it may not seal very well! The KLX300 header will have a larger I.D. than the muffler O.D.

 

Thank you very much for the clarification. Now that I have the 300 pipe I'll be patient and wait for a 300 muffler. My uncorked 250 muffler makes just the right amount of noise. A friend of mine has a FMF and it's too loud for my taste.