For those who went up to the 300 cc, is anyone running it with the stock header? I'm not ready to do the kit right now, but I have a lead (finally) on a stock klx300 header and I'm trying to decide when I do go big if I'm going to runA: stock header and HMF slip-on or B: klx 300 header and silencer.

 

<Raising hand>

300cc
300 header
Pro Circuit 496
Open Box
DJ kit

 

Oh ya, I went with the Weisco piston too--might as well--its cheaper & forged.

 

The guys at thumper talk, which is comprised of mostly KLX300 riders, will tell you that the head pipe has to go. However, Marty is running a 331 with HMF and stock pipe. He seems to like it just fine. You might want to drop him a few lines at klrworld.com.

 

fireroad i have a klx 300 with the stock header and a procircuit T-4,modified air box and 13-50 gears.my setup works really good.has a lot of tork on the bottom end,tyhat's how i like it.

 

I would say if you are doing a lot of tight trails the stock headpipe isthe weapon of choice.If you have some dinero to burn, FMF makes a 250SPowerBomb header that is supposed to even further improve low-end torque while maintaining asolid top-end.The complete FMF system is a bit pricey though.

 

Fireroad I am not sure if you know or not but the 300 header and the 250s header are the same except for length. The 300 header does allow you to run slipons designed for the 300, but the market has come around for 250s slipons with the stock. My opinion, based on what I have read from 300 owners is that the stock header dia. is too small. A different option to look into would be get a stock 300 muffler and get a FSW header which is larger dia. than stock.

 

Okay, so if I understand you correctly the stock 300 and 250s headers are the same inside diameter...the 300 is longer....then the300 must have a flange on the end of it as the 300 muffler inlet is wider in diameter then the 250s muffler? There is no advantage to running a stock 300 header other than being able to use 300 slip-ons?

 

Correct, and correct. Alot of guys were running them in the begining because there were no slipons for the 250s only the 300. And some guys were running the full 300 exhaust because it is some improvement over stock 250s and can be had for very cheap on ebay. As far as performance goes there is no difference between the 250s and the 300 header.

 

Good to know rather than waste the $ and time for nothing