I have an opportunity to get a K&N filter and outerwear somewhat cheap from a friend, and I was wondering if it is necessary to rejet a stock Quadrunner 500 (LTF-500F)after putting it on. If so, is rejetting one of these quads a big deal? I only have experience on bigger engines. Also, has anyone noticed a performance increase after putting JUST the filter on? I know it's a trivial question, but I have no clue. Thanks!

 

Generally, no you don't have to re-jet. You should notice a difference. See the quadmaster trouble post. Our discussion veered into K&Ns. Notice the post where I've heard K&N's are not desireable for sand dunes though.