I just recently purchased a new KLX250S. I have read so many forums that I'm not sure what to do to get this thing to zoom. I live in Denver so I don't know if alot of what has been posted will apply to 5000-9000ft. Do I need an all new exhaust or will drilling out factory exhaust be good. I spoke to Kawi Dealer today and they said if I put on new Big Gun Exhaust I do not have to put jet kit, just rejet. Will DynoKit be better or just rejet. Could somebody please clear this up for me. Thanks

 

There is a heck of a KLX section here. Post those same questions down in that area, and you will be covered!

Congrats on the new ride.

btw, Welcome to the forums.....

 

Welcome to the forums! The guys in the KLX section will definately be able to help you out!

 

welcome to KF. their right check out the KLX area some body should have those anserws for ya. congrats on ur new ride.

 

welcome to the forum. Hope someone here can be of some help.

 

Come to the dark side.


https://www.kawasakiforums.com/forumid_69/tt.htm

 

You do need to rejet after installing an aftermarket pipe such as the Big Gun or Muzzy, otherwise, you'll be running too lean which can be damaging. Dynojet is just a brand name kit with a few different jets, needle, etc. If you know what you need, you can save some $$ and just buy the jets and needle seperately. If you need to experiment with different jet sizes, the Dynojet may meet your needs.

Regarding drilling out the stock exhaust vs something like the Big Gun or Muzzy pipe, the Big Gun or Muzzy will be better. Drilling is nice because it helps and it is free. Another option is to find a stock KLX300 pipe which can be had cheap if you look around. This is a better pipe than the KLX250S stock pipe and can be a very economical pipe upgrade. One word of warning - stay away from KLX300 "slip-ons". The head pipes differ enough between the KLX250S and the KLX300 such that a KLX300 slip-on will not work on the KLX250S. However, a KLX300 full system (muffler + mid + head pipe) will bolt onto the KLX250S just fine. This is important because the KLX250S is too new to the U.S. for any aftermarket pipe manufacturers to make a KLX250S specific pipe. Thus, we are all buying KLX300 pipes since those are the only options available at this time. Full system works fine, but "slip-ons" don't.

For a good starting place on the procedures and jet sizes that work for others, see the KLX250S forum under the dual sport section. At the top, you will see a handfull of "sticky" threads that detail the standard mods folks find most beneficial. Some of the most beneficial are zero or low-cost. You can really wake this bike up by rejetting, replacing the stock needle with an adjustable one, adjusting the pilot screw out a bit, replacing the stock airbox snorkel with a high flow part, drilling the first baffle of the stock pipe, and opening up the crankcase breather vent to 3/8". Specifically, see here for more information - if anything is unclear, just ask:

https://www.kawasakiforums.com/m_32128/tm.htm

Here's the link to the main forum:

https://www.kawasakiforums.com/forumid_69/tt.htm

Cheers,