Just got a K&N for my '01 Scrambler 400 where do I need to go with the jetting? I got a 240 main when I bought the filter but they didn't have a 250 is the 240 enough or do I need to find a 250 before riding it? I don't really want to change it more than once this week. I am drag racing it Thursday and riding in a rodeo on Saturday. Thanks for the help.

Your 240 should be fine unless you have made air box mods as well, then go to a 250. Drop the clip on the needle by one (raise the needle) as mid range burn down is the most common problem with the 400, not top end.

There is no reason to touch the needle, leave it alone. What temperature and elevation are you racing in? These are both factors for your jetting.

you should NOT have to rejet for a k&n unless its an open cone that replaces the airbox.a 240 main jet should be more than enuff.check your plug frequently as weather changes to keep it a chocolate brown color.

I'm at about 400' above sea level. Temps will probably in the 80's high humidity. Thanks for the responses guys.

The K&N is a little overrated, A good filter but no re-jetting required, Before I did my mods i actually went down to a 220 with my K&N to quit wasting plugs, the 230 is more than enough to cover the filter, Just do a couple plug checks to be safe . [img]i/expressions/face-icon-small-wink.gif[/img]

Stick with the 230.