Hmmm what exactly are airbox vents, I mean I can assume they are vents in the airbox [img]i/expressions/face-icon-small-smile.gif[/img] but how do I make them. I have the K&N in and have run it for probably 4 hours since then, is this bad that I am doing this without vents, or am I just restricting the potential it has?

 

no, the vent will just help it to get a little more air, but all you do it drill the size hole it tells you to do then just pop them in. I had a 250ex and your not going to get to much more power out of it.

 

Ic, where would I drill these holes, on the cover to the air filter box?

 

Yes, drill the cover. You can get the vents at rockymountainatv.com

 

Well I got the exhaust today, installed the exhaust and jets. It's extremely loud, haven't put in the sound limiter or whatever it's called. But the reason I am posting here is because I believe the jets are flooding it or starving it. The main jet went from 95 to 100. The pilot idk what the change was atm but I will try and find out. Anyway it runs fine while the throttle is down, but can't idle for more than 2 seconds without cutting out. Can you tell whether or not the jets are overfilling or underfilling it.
*NOTE I ALSO HAVE A K&N AIR FILTER*

 

Update:
Just adjusted the idling speed to increase it and it seems to idle well, although I'd prefer it back to normal, so advice is still welcome!!

 

To continue my talk to myself :-P there is a noticeable power increase, for my tiny weight I find it far easier to hold wheelies. Anyway, I'm hoping that the jetting which may be off, isn't harming the engine at all. Fixing the stalling was just temporary, I want to get this thing to the ideal settings for throttle response and longevity. If anybody has any input/advice I could use anything sensible, b/c I'm a total noob with mechanics!

 

im juist installing a 300ex motor in my 250 that should make it faster..when I had the 250x motor it was piped and jetted and I ran with no air box lid ...

 

Hmmm, I think I'll go over to my machine and take off the lid and try to run it, see what happens if I turn down the idling speed. Can this harm my atv at all or allow dirt/water into the airbox?

 

The results were good! Turned down the idle to below what it was stock and it runs, so I turned it to what I think it used to be as stock.