So I was looking at a post and didnt want to steel it. I have an 06 KLX250s and I have seen that a lot if not all of you seem to be removing this system.

WHAT DOES IT DO and what improvements will I get by removing it? Is it as simple as plugging the hole in the air box, the carb, and the hose coming out of the front of the motor near the exhaust manifold? Do I need to do anyhting else for this mod in particular???

I am in the process of putting on an HMF exhaust, I have done a crank case breather mod, and Gutted the mesh screen out of my intake. I am running UNI filters and have the high flow intake snorkel.

Am I better off running the high flow snorkel or just running without an airbox lid?

Also, I have been looking at the dynojet kit for the klx300r but would I be better to switch to a different carb?

THANKS!!!

MAXXXXX

 

No lid is how I ride. Goes like a raped ape.

 

IMHO Dynojet has the best needle profile for this bike. $$$ over the OE Kehein parts though.

 

That smog system does nothing for performance so leave it on if you want. Some guys are running no lid at all with good results and some(like me) have the lid on with the a 4x4 hole cut in it. You'll have to decide what works best for your bike once you start jetting it. The klx 300 jet kit is all you really need unless your looking for a sizable power increase and then you'd have to get a big bore kit. An aftermarket carb won't get you much so save that money for when you decide you want the big bore.

 

The system injects fresh air from the air box into the header to "promote unburned fuel to burn" *cough dillute cough* tail pipe emissions down. It does not help or hurt performace. Cap the air box & the head or better yet get a block off plate from Bill Blue.

Pros: gets rid of some off throttle popping, eases spark plug & top of engine area access, & saves a few ounces.

I run the DJ 300 kit @ 292cc, slip on, no lid, all per DJ settings for such.

I have done the high flow snorkel--just bin it instead.

 

removing that stuff allows the engine to rev more freely, just like unblocking the crank vent.